Top Banner
193

Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

Jun 27, 2020

Download

Documents

dariahiddleston
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Page 1: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♥sttt P②sq t ♠ s tér① trs♦r

ès ♦t♦rt ❯♥rsté trs♦r

♠♣t ♦ strtr ts

♦♥ s♣♥♣♦r③ tr♥s♣♦rt

r♦ss ♠♥t t♥♥ ♥t♦♥s

♣r

P

♦t♥ ♣q♠♥t ♠r ♥t r② ♦♠♣♦sé

s r②ss rtr tèsr♥ç♦s ♦♥t♥ ♣♣♦rtrréér Ptr♦ ♣♣♦rtr❲♦♥ ❲r ①♠♥tr ♥tr♥

Page 2: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue
Page 3: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♥♦♠♥ts

② t t♠ ♠ rt♥ ts ♦rs t s r② ♥ ♦r ②s s♥ t♠♠♦r tr♥♦♦♥ ♥ ♦② r ♠② P ♣♦♠ ♥s♦♥ t t ♠♥sr♣t ②♦ r ♦♥ ♥ ♥s ♦r ♠♦r ♣r♦② ts t♦♣② s♠♠r③s ♠♦r t♥ tr ②rs ♦ t ♦r ♣r♦r♠ r♥ ♠②st② t t P ♥sttt ♦r ts ♣ rs s♣ s♥♥ ♦r♠ ♦♥t ①♣t ♦ t tt r ♥ ♥ t r② ♠♦r♥♥ ♦♣t♠r r♦ss t P♦♥t ♥ ♦r t rst t♠ st r ♠② rst♦r♥② ② tr♥ t♦ t ❯♥rst② ♦ ♦s r♥ ♣t ③♥ tr♦t ♥♦ t ♥♠r♦s sts ♦ t ❱♦ss ♦♥t♥s ♥ ♥ ttt s s s♦♠♦ r♥t tt ♠ st ♣ssr② ♥ tt ♦ ♥r ts ♣s ♠♥ t t ❯♥rst② ♦ trs♦r ♥ t s ♥♥ r♥ ♥r r♠♥ r r♦♠ t ♦ ♠② ♦♥t♠ r♥s ♥t ①t♥s ♦r s♥ ♦♦ts ♥ s♦ ♥ r r② s♥♣ s ♦♠ ♦r ♠ t ♥ ♥r♦♥♠♥t t ♥ ♠♥② ②s tr② ♥♥st② r♥t s♣② s ♥♦t s♣ s♥ ♦r ♥ r♥ ♣♦♥rr

t s r t♦ s② t ♣♦♥t strt t♦ s ♦♠ ♥ ♣♦♣r r♥s ♥♥♦t r ♥ t st♦♣ st②♥ ♠♣s s r②♥♦♥ t♠ ② rt ♦♥t r♠♠r ♥ ♥t ♣♦♣ strt t♦ s ♠ ♦tt st tr ♦rs t♦ tr r♦♥ ♥ ♥ strt t♦ ♥sr t♠ ♥ tr♥t ♥ tr ♠♦r t♥ ts ♦r ②rs s♣♥t r ♦♥t t♦ ♦r rs♦♥s ♦r ts ② ♥♥♦t ①s② ttrt♥tr t♦ t t② ♦ s ♥♦r t♦ t ♦ rsr ♥ t P ♦♥②t s s♦ t ♣♦♣ ♦r t

♦ t♦ s② ♦t ♦ ♥ ②♦ t♦ r②♦♥ ♦ ♣ ♠ tr♦♦tt t♠r♠ ♦ ts tss tr② t rst ♦♥ ♦s t♦ rt♥ ♦♥ ♠② t♦ ♦ss ♦ s ♠ tr♦♦t t ♥tr ♥t ♦ t rsr ♣r♦r♠♥ ♦ s ♠② ♣r♠r② s♦r ♦ ♠♦st ♦ t ♥♦ tt ♣♦sss ♥♦ ♦ t♦ t♥ ♣♦♣ r♦♠ t r♦♣ t ♦♠ ♦♣♣♦rt♥t②♥ ♣sr t♦ ♦r s♣② rs r r♣r ♠② ♦rs r②ss rst♦♣ r ♦♥ ♠ ♥♦ t ❯♥rst② ♦ rs ♥♦♥ ♠ ② ♠♠r ♥ ❱r♦♥q ❲r♥r

♦r♦r ♦ ♥♦t ♦rt ♦t ♣♦♣ r ♥♦t ♠♠rs ♦ t

Page 4: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

r♦♣ t t♦t ♦s ssst♥ ♠② rsr ♦ ♥♦t ♣r♦ ♥② rtrs♣② ♦s tt rt ♥ ♦♠♥q ♥ssst♥t ♥♥r

♥ s♣rts ♣r♦ss♦♥ ♦♥tts ♥ t ♣rt ♦ ②♦♥s♥tst s ♥♦t s② t♦ r ♦r t rt♥② r♥s s♦♠r r♦ss ♦s♦ ♦ st♥ts ♦ sr ♦t ♦② ♥ ♠sr② ♦ tr ♦s ♦♠ ♦②♦ ♥♦ ttr s♦♠ ss t♦ t♥ ♦ ②♦ ♦r t t♠ s♣♥t t♦tr rst♥ ♥rs ♥♣tst r♥ ♥ ss s♠ ♦♦ ❱♥♥t s♥ t♠ ♦ ❱♥ r♠r③ ♥♦P♦st♦ ♥ rr r ♦♠♠ r ♥♦ ♣♥t r♥♦ ❯ s♠r ♦♠ ♠ ♥♦♦♥ ♦t♠ r♠ r③♥ trs ♦ ♥♦ ❯♣♣s ❯♥rst② r ❲♦ ③ ♠tr ❳♥♦t ❩♥tt♥ ♥ ❾s③ ❩♦s

♦st ♣rs♦♥② t♥ ♠② tr ♦s s③♦ ♦ s ②s ♦s t♦ ♠♥♦ ♠ttr ♦ r ♠② ♠♠ ♥ r♥♣r♥ts ♦r rst♥ ♦ ♥ t ♥♠

♦r♦r ♦ t♦ t♥ ♣r♦ ♥ s③ r♦♠ t ❲r♦ ❯♥rst②♦ ♥♦♦② ♦r t ♣♦sst② ♦ ♣r♦r♠♥ ♣rt ♦ ♠② sts t t ❯♥rst②♦ trs♦r t♥s t♦ t ♦♦♣rt♦♥ t♥ r♦♥s ♦ s ♥ ♦r ss s t♥ ♦t ❯♥rsts

Page 5: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue
Page 6: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue
Page 7: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♦♥t♥ts

és♠é ♥ r♥çs

♥tr♦t♦♥

♦rt ss

ss ♦ ♥♥ ♥t♦rsst♥ r♦♠ s♠♣ t♦ ♣t① rrrs ♦♥③r♦ s♣♥ ♣♦r③t♦♥ ♥ rr♦♠♥ts ♣♥♣♦r③ t♥♥♥ ♥ ♠♥t t♥♥ ♥t♦♥s ②♠♠tr② tr♥ ♥

tr♦♥ ♦ ♥t♦♥s ♥ strtrs ♠♣t

♥s♠ ① r♦♥

r♥s♣♦rt t♦♥s ♥tr♥s sss

❩r♦ s ♥♦♠② ♥tr rs♦♥♥t stts ♠♣t ♦ ♣♦♥♦♥s

tr rrr t②♣s tr♦♥t♠ tt♥t t♥♠ ♦①

r♥t tr♦ ♠trs ♥tr♦t♦♥ ♦ ♦t

♦tr♦♥ ♦②s ♥tr ♦t ②rs

♦ s t①tr s②st♠s 0.7r0.3♥3 ♠t tr♦s

r②st s♣tt♥ ♦ ①♥ ♠♥s♠

Page 8: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♠♣rtr ♣♥♥ s②st♠

♦ ♦ ts ♠♣rt♦♥s

♠♣t ♦♥ s♣♥♣♦r③ tr♥s♣♦rt ♣t tt② ♥ r②st♥ s②st♠s

♥s♠ ♦① tr♦♥t♠ tt♥t t♥♠ ♦①

♥tr sss ①t♦♥ ♦♥sq♥s ♦ ♥♥♥

♥tr ♦① ②r ♦r♠t♦♥ s♦♥ ♦ ♠trs ♠♦♥ t ②rs

❯♥rt♥ ♥tr tr♠♥t♦♥ tr♦♠rt♦♥ ♥ srt♥ t♥ ♠♥ts♠ ♦♥s♦♥s

①♣r♠♥t r③t♦♥

♠♣ r♦t t♥qs ♥ ♦♣♠♥t ❯tr ♠ ♣♠♣♥ s②st♠s strt ♣r♣rt♦♥ ♣ttr♥

②r ②st♠ s♣ttr♥ ♥② ♣ttr♥

♣♦rt♦♥ Ps sr ♣♦st♦♥

t♦♥ ♥r② tr♦♥ rt♦♥

r♦♠ s♠♣s t♦ s ♥st ♣ttr♥ ♣t t♦r♣②

t♦r♣② ♠s P♦t♦rssts

P♦st ♣♦t♦rsst t ♣♦t♦rsst ❩

Pr♦ss♥ P♦t♦rsst ♣♦st♦♥ ♥ ts t♦r♥ P Pr ♥t♦♥

Page 9: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ♦r tr♦ ♥t♦♥ P Psst♦♥ ②r ♣♦st♦♥ P ❱ t③t♦♥

sst♥ ♣r♦♥ ♥ ♦♥tt ♠♦s ♦♣♦♥t ♠sr♠♥t ♦ t ♦♥tts ♦r♣♦♥t ♥t♦♥ st② sst♥r ♣r♦ts

♠♦♥ s t ♥♣ ♠♦♥t ♥ r♦♥♥

st② ♣♣rts ♥ t♥qs st♣ ♣ts ①♣r♠♥t tr♠♥t♦♥ ♦ t rrr ♣♦t♥t ♥s♣

rt ❱ rtrsts ♥②ss g ♠t♦ I ♠t♦ ❱♦tt♠♣rtr ♣♥♥② ♠♣s

♣t sts

st②

r♥st♦♥ ♠t ♦①s tr♦♥t♠ tt♥t

♦♣t tt② ♦2r3♦2

t♥♠ ♦① ♦22♦2 ♦2♦

♦♥s♦♥s ♥ ♠♦ t♦rs

♥s♠ ♦① rrr sts

♣t tt② tr ♠sr♠♥ts

♦♦

♥r ♣r♦♣rts ♥②ss ♦ t ❱ ♣r♠tr s♣

♥ ❱ s♣ ♥♥ s②st♠ ♥♦♥♥♥ s②st♠

Page 10: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❱ ♦♥s♦♥s ♥ ♣rs♣ts

♠♠r② r♥st♦♥ ♠t ♦①s ♥s♠ ♦①

♦♠♣ r♥st♦♥ ♠t ♦①s ♥s♠ ♦① ♣t ss

♦r♣②

Page 11: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue
Page 12: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue
Page 13: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

és♠é ♥ r♥çs

étr♦♥ ût ÷r ré♦t♦♥s t♥♦♦qs q ♠♦èr♥t ♣r♦♦♥é♠♥t s♦été ♥s ①è♠ ♠♦té sè ♣réé♥t ♥♦t♠♠♥t è♥♠♥t ♦r♥tr ♣rs♦♥♥ t ♣♣rt♦♥ ♥♦① ♠♦②♥s ♦♠♠♥t♦♥sq ré♠♠♥t ① ♣r♦♣rétés ♥tr♥sèqs étr♦♥ r♥t tsés ♥ss ér♥ts t♥♦♦s r étr♦♥ tsé ♥s t♦t s s♣♦sts étr♦♥qs ssqs ♦♥trôé ♠♦②♥ ♥ ♠♣ étrq t s♦♥s♣♥ tsé à trrs ss ♠♥stt♦♥s ♠r♦s♦♣qs ♣♦r s ♥rstr♠♥ts♠♥étqs ♣r ①♠♣ ♣♥♥t s ① ♣r♦♣rétés ♥♥t ♠s été tsés ♥ ss♦t♦♥ ♣♦r ♦♠♣r ♥ t ♣rés st ♣résé♠♥t à r♦s♠♥tq♥tr♥t s♣♥tr♦♥q s♦♥ ♦t st ♠♦r ♠♦♠♥t s étr♦♥s t ♦♥ ♦♥t♦♥ étrq ♥ ss♥t sr s♣♥ à ♥ ♠♣♠♥étq ①térr

♥ q s♣♥ étr♦♥ s♦t ♦♥♥ t été ♣s ♥♦♠rss ♥♥éssq très ré♠♠♥t s♦♥ tst♦♥ ♥ tr♠ ♣♣t♦♥ à été ♥éé ♥ é♦rt ♠♥ét♦résst♥ é♥t ♣r rt rt t ♥é♣♥♠♠♥t ♣r Ptr r♥r à r♣♠♥t ttré tt♥t♦♥ ♦♠♠♥tés♥tq sr tr♥s♣♦rt étr♦♥q é♣♥♥t s♣♥ ♥s s ♠tér①♦♥sst♥t ♥ ♥ sss♦♥ ♥s ♦s rr♦♠♥étq t ♥♦♥ ♠♥étq é♣ssrs ♥♥♦♠étrqs ♥s ts s②stè♠s st ♣♦ss ♥r résst♥ ♥ ♠♦♥t ♦♥rt♦♥ ♠♥tt♦♥ s étr♦srr♦♠♥étqs ♥ étt ♣rè P à ♥ étt ♥t♣rè P ♥ ♣♣q♥t♥ ♠♣ ①tr♥ ♣r ①♠♣ ♥ ♦♦r ♦sré ♥ ♥♠♥t résst♥ ♥♦r ♣s ♠♣♦rt♥t ♥s s strtrs ♦♠♣♦sés étr♦s rr♦♠♥étqs sé♣rés ♣r ♥ ♥ ♦ ♠tér ♥♦♥ ♦♥tr tsstrtrs s♦♥t ♣♣és s ♦♥t♦♥s t♥♥s ♠♥étqs ♥♠♥t résst♥ ♥s s s②stè♠s à été ♣♣é ♠♥ét♦résst♥ t♥♥ r s étr♦♥s s♦♥t tr♥sérés ♥ étr♦ à ♥ tr ♣r t t♥♥ ♠♥ét♦résst♥ st é♥ ♦♠♠ rt♦♥ rt résst♥ ♥tr étt♣rè t ♥t♣rè TMR = (RAP −RP )/RP

♦r♥ ♠♥ét♦résst♥ ♥s s ♣r♦♥t ér♥ ♥sté étts à é♥r r♠ ♥tr ♣♦♣t♦♥ s♣♥ ♣ t ♦♥ ♥s s ♠tér① rr♦♠♥étqs tt ér♥ st rtérsé ♣r ♣♦rst♦♥ s♣♥ é♥t ♣r P = (N↑ −N↓)/(N↑ +N↓) ♥♦s s♣♣♦s♦♥s

Page 14: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♦♥srt♦♥ s♣♥ ♦rs tr♥s♣♦rt ♥ étr♦♥ ♣t ♣ssr ♣r t t♥♥ àtrrs rrèr s♠♥t s ♥ étt ♣♦ssé♥t ♠è♠ s♣♥ st ss ♥s ①è♠ étr♦ ♥sté étt ss ♣♦r ♥ étr♦♥ r ♦♥rt♦♥ rt ♠♥tt♦♥ s étr♦s ♣rè ♦ ♥t♣rè t♦♥t à ♥ ér♥ résst♥ ♥tr s ① étts

♠é♦rt♦♥ s t♥qs ①♣ér♠♥ts st ♣♦ss ♦r rqr s t♦t♠♥t é♣t①és ♥s s s②stè♠s s t♦♠s s♦♥t ♠♣és ♠♥èr ♦r♦♥♥é t s étr♦♥s ♣♥t ètr érts ♣r s ♦♥t♦♥s ♦♥ ♦ ♣s té♦r s r♦♣s ♣r♠t ssr s étr♦♥s ♥ ♦♥t♦♥ ss②♠étrs s ♦rts ♦♣és s s②♠étrs s ♦♥t♦♥s ♦♥ ♦ ♦♥t♥ rô ♠♣♦rt♥t ♥s tr♥s♣♦rt t♥♥ ♥s s s②stè♠s é♣t①és t q rrèr s♦t ss rst♥ ♣r♠t ♦♥srr s②♠étr s étr♦♥s♦rs tr♥srt à trrs rrèr ♦♥ ♣r tr♥s♣♦rt étrq ♦ér♥t s ér♥ts s②♠étrs s ♦♥t♦♥s ♦♥ ♦ s♦♥t tté♥és ♠♥èrér♥t ♥s rrèr st ♥s ♣♦ss trr s ér♥ts s②♠étrs ♥s rrèr t ♦♥♥trr tr♥s♣♦rt sr s s②♠étrs t♦t♠♥t ♣♦rsés àé♥r r♠ ♠♣♦rt♥ts rs ♣♥t ♥s ètr ♦t♥s s s rrèrs ♦♠♣♦sés t r3 s♦♥t s ♥ts ♣♦t♥ts♣♦r ♣r♦♥ é♥ért♦♥ s♣♦sts s♣♥tr♦♥qs

♥ s tr① té♦rqs ♦♥t ♣rét s rs ♠♥ét♦résst♥s ♣s ♥s s s②stè♠s t♦t♠♥t é♣t①és ♥ q s ♣rét♦♥s ♥t été és ①♣ér♠♥t♠♥t ①st ♥♦r ♦rts ér♥s♥tr s rs ♣réts t s réstts ①♣ér♠♥t① tt ér♥ st ♣r♥♣♠♥t t q st ①trè♠♠♥t rér ♥ s②stè♠ ♣rt ①♣ér♠♥t♠♥t t ♣srs ♣é♥♦♠è♥s s♦♥t rs♣♦♥ss s rt♠♥t srs ♦t♥s s ♣é♥♦♠è♥s ♦①②t♦♥s t s♦♥s s♦♥t à ♦r♥ ♣♣rt♦♥ ♦s s♣♣é♠♥tr ① ♥trs q ♣♥t ♦r sts ♥ésrs t ss rér ♠♥ét♦résst♥ s éts ♥s rrèrrst♥ ♣♥t é♠♥t ♦r ♥ ♠♣t ♥ésr sr ♠♥ét♦résst♥♥ t s éts rés♥t tr ♠♦②♥♥ rrèr t ré♥t s ♥① ♦♥t♦♥ ♣♦r s étr♦♥s ♥é♣♥♠♠♥t rs s②♠étrs

♦♠♣r♥r ♣②sq s éts ♥s s st ♦♥ très ♠♣♦rt♥t ♥t ♣t ♣r♠ttr rér s ♦♥t♦♥s ♠rs qtés s♣r♦♣rétés ♦♣t♠sés t ♥s s r♣♣r♦r s rs té♦rqs s st é♠♥t ♣♦ss tsr s éts ♣♦r rér s s♣♦sts ♣♦ssé♥t ♥♦s♦♥t♦♥♥tés ♦♠♠ s ♦♥t♦♥s s ♣r♦♣rétés ♠♠rsts ♣r ①♠♣ ①st ér♥ts ♠ét♦s ♣♦r étr s éts ♥s s s ♠srs ♠♥ét♦tr♥s♣♦rt ♥ t♠♣értr ♣r♠tt♥t ér ① trs rrèr① ♥trs ♥s qà trs ♣é♥♦♠è♥s tr♠q♠♥t tés s ♠srs♦♣tqs ♣r♠tt♥t é♠♥t ♦t♥r ♣réss ♥♦r♠t♦♥s sr t②♣ éts tt tès ♣♦r ♦t ♦rr ♦ à ♦♠♣ré♥s♦♥ ♠♣ts éts sr tr♥s♣♦rt t♥♥ ♥s s rst♥s

Page 15: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

s ♦♥t♦♥s t♥♥s s rrèrs t r3 ♥s q s é♥t♦♥s ♦♥t♥♥t s♠♥t s rrèrs r♥t rqés ♣r ♣érst♦♥ t♦q t ♣r P ♣s sr ♣♦st♦♥ rt♥s s é♥t♦♥s ♦♥t été rqés ♥ ♦♦rt♦♥ ♥tr♥ trs é♣rt♠♥ts à P ♥♦t♠♠♥t ♣♦r s é♣♦st♦♥s P ♦ ♥ ♦♦rt♦♥ ①tr♥ ♥♦t♠♠♥t ♥ é♣rt♠♥t P ♥sttt ♥ ♠♦r ♥② ♣♦r sé♥t♦♥s ♦♦

s ①♣ér♥s tés sr s rqés ♣r ♣érst♦♥ t♦q s rrèrs ♠♦♥tr♥t q rt♥ t②♣s éts ♥s strtr rst♥ rrèr ♣♥t ètr é♠♥és ♥ rq♥t s é♥t♦♥s♥s rt♥s ♦♥t♦♥s é♣ôt s rrèrs ♥♠ ♦♥t étérqés ér♥t t① ♦①②è♥s é♣ôt t s ①♣ér♥s ♦♣tqs ♦♥tété tés s réstts ♠♦♥tr♥t q♥ ♠♥tt♦♥ rt♦ ♦①②è♥r♦♥à ♣♦r t rér s ♣s s♦r♣t♦♥ à s é♥rs q ♦rrs♣♦♥♥t ①s♦r♣t♦♥s ♦♣tqs éts ♣ès

s ♣s s♦r♣t♦♥ à ❱ ♦rrs♣♦♥♥t à ♦♠♥s♦♥ ① ♥s♦①②è♥ ♥trs F2 s ♣s à ❱ ♦rrs♣♦♥♥t à ♥ ♥ ♦①②è♥ ♥tr♦ ♦♥sé F F+ t♥s q s ♣s à ❱ ♦rrs♣♦♥♥t à ♥ ♥ ♦①②è♥ ♦♠♥t ♦♥sé F+

2 s ♣s rést♥t s ♥trs FF+ s♣rss♥t s♣tr s♦r♣t♦♥ ♣♦r ♥ rst é♣♦sé ♥s ♥ t♠♦s♣èr ♦♠♣♦sé ♦①②è♥ t r♦♥ s réstts sèr♥t s♣rt♦♥ séts ♥s strtr rst♥

♥ ♦♥r♠r tt ②♣♦tès s é♥t♦♥s ♥♠♥♠ r♥trqés s rt♦s ♦①②è♥r♦♥ t s ①♣ér♥s ♠♦♥tr♥t q ♦ tr♥ ♣♦ssè ♠♦♥s ♦ts♣♦ts ♣♦♥ts ♣s♦♥trs ♦rsq t♠♦s♣èr st ♥r ♥ ♦①②è♥ été éré q sréstts ♥ s♦♥t ♣s és à s ér♥s t♦♣♦r♣

s♣rt♦♥ s ♣s FF+ s♣tr s♦r♣t♦♥ t ♠é♦rt♦♥ s ♣r♦♣rétés s é♥t♦♥s ♦rrs♣♦♥♥ts ♦♥♦rt é s♦♥ q s ♥trs Fs♦♥t rs♣♦♥ss ♠♦rté tr♥s♣♦rt étr♦♥q ♥s rrèr û ① éts P♦r ♦♥r♠r s ♦r ♦r♥t♦t ♦♥t été ♠sréssr s ① t②♣s é♥t♦♥s ♦♠♣rs♦♥ s ♦♥♥és ♣♦r ♥ t♥s♦♥♣♣qé ♣♦st ♦rrs♣♦♥♥t à ♥tr s♣érr ♦♥♥ s ♥♦r♠t♦♥s♣rt♥♥ts sr ♣rés♥ s éts t r ♠♣t sr tr♥s♣♦rt t♥♥ tr rrèr ♣ss ❱ à ❱❱ ♥s rrèr♣♥ t ❱ à❱ sr s ♦ts♣♦ts ♦♥ ss♠ q é♥r r♠ s tr♦ ♠ ♣ ♦rs tr t rrèr sr ❱ à s ♥trsF t F+ stés à ❱ ♥s rrèr ♣s s♣rt♦♥ ♣ ♦♥t♥ à ❱ ♥s s ♦rs ❱ sr é♥t♦♥ rqé ♦①②è♥♦♥r♠ ♥ q ♦♥t♥ ①ss ♣r♦♥t s sts F t F+ qs♦♥t é♠♥és ♥s s ♦♥t♦♥s é♣ôt

Psrs é♥t♦♥s ♦♥t été rqés ♥ ♦♦rt♦♥ ♥sttt ♥

Page 16: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♠♦r ♥② s ♣r♠rs é♥t♦♥s s♦♥t s étér♦strtrs t②♣ ♦♦ sr sqs s ♠srs ♠♥ét♦tr♥s♣♦rt ♦♥t été tés s♦♥ t②♣ é♥t♦♥ ♦♥r♥ s étér♦strtrs ♥ ♣♦ssé♥t ♣s ♦♥tr étr♦ rrèr st ♦rs r♥èr ♦ strtrs ♠srs ♣♦t♦♠♥s♥ ♦♥t été tés ♥s t étr♠♥r ♠♣t rt sr tr♥s♣♦rt étr♦♥q à trrs ts ♦♥t♦♥s P♦r qt②♣ étér♦strtrs s é♥t♦♥s rts à ♥s q s é♥t♦♥s♥♦♥ rts ♦♥t été étés t ♦♠♣rés

s ♣s ♦srés ♦rs ♠srs ♣♦t♦♠♥s♥ tés à ér♥ts♦♥rs ♦♥ ♣r♠tt♥t étr♠♥r é♥r s éts ♥tr♦ts ♣s s♥s ♦①②è♥ ♥s rrèr s ♦srt♦♥s s♦♥t ♥ ♦r trstr①éts ♣rés♥ts ♥s ttértr rt♦♥ ♦♥t♦♥s t♥♥ ♠♥étq été té ♣r ♥ ♣r♦t♦♦ t♦r♣ st♥r s ♦♥t♦♥s♥s ♦t♥s ♣rés♥t♥t ♥ ♣r♦t ♥♦r♠ réstt sèr q é♥t♦♥ st ♦♠♥t ♦♠♦è♥ s ♠srs ♠♥étqs tés à t♠♣értr♠♥t s♦♥t ♦ér♥ts s ♠srs ♠♥étst♦♥ té à ♥❯ ♥s s s é♥t♦♥s ♥♦♥ rts étt ♥t♣rè ♥st ♣s ♥é♥ rést♥t ♥ ♥ s♥ ♥ r♥ sr s é♥t♦♥s rtétt ♥t♣rè st ♥ é♥t t ♦sré st ♣s ♥s s t é♠♥t ♣r♥r ♥ ♦♠♣t rstst♦♥ rrèr ♦rs rt ♣s ♥♦s ♦sr♦♥s sr s é♥t♦♥s ♥♦♥ rts q tr rrèr st ♥tq ♥s étt ♣rè t ♥t♣rè ♦rs q st ♥é♥s s s é♥t♦♥s rts ❱ ♣♦r P t ❱ ♣♦r P

é♣♥♥ ♥ t♠♣értr résst♥ ♥s q ♠♥ét♦résst♥ ♠♦♥tr♥t ♥ ♥♠♥t ré♠ à ♥s s ① s rt t ♥♦♥rt ♣♦♥t sr str ♣s tr ♥ ♣t é♠♥t ♦srr ♥ ♣tà ♣rtr sq① ♣s s t♠♣értrs ♥s s s s é♥t♦♥srts ♣rés♥ ♣t ♣t êtr ttré à s♥ éts srt♦♥s ♠♥ét♦résst♥ ♥ ♦♥t♦♥ t♥s♦♥ t t♠♣értr❱ ♠♦♥tr♥t q ♠♥ ♣s r♣♠♥t ♥ t♥s♦♥ t ♥ t♠♣értr ♥s s s é♥t♦♥s rts

♥②s s ♥① ♦♥t♦♥ tr♠q♠♥t té sr s ♦♥t♦♥s rts ♠♦♥tr ♥ ♠♥t♦♥ r♣ ♥ ♦♥t♦♥ t♠♣értr t♦r ❱ tt t ♣t êtr ttré ① sts F t F+ ♥ ♦♠♣r♥r s♣é♥♦♠è♥s és à tt♦♥ tr♠q ♦♥t♥ ♥s q s ér♥s tr rrèr ♥ ét rt♦♥ ♦♥tté ♥ ♦♥t♦♥ t♠♣értr été té ss ♣♣é ♣ ♦ ❰ ♦♥tté é♥t♦♥ ♥♦♥ rt st ♦♠♥é ♣r tr♥s♠ss♦♥ ♣♦rtr rs s ♥trs F F+ t F+∗ à ♣rtr s ♦♥tté st ♦♠♥é ♣r s stsF+∗ sq t♠♣értr à ♣rtr q tr♥s♣♦rt st ♦♠♥é ♣r s♥trs F2 P♦r tt rs♦♥ ♥ ♠♥t♦♥ s♥t résst♥ st ♦sré à tt t♠♣értr ♥s s s ♦♥t♦♥s rts ♠♥tt♦♥

Page 17: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♦♥tté ♥ ss♦s st ♦♠♥é ♣r s ts strtr ♥ ♥s s P ♦rs q♥ t s♠r ♥♣♣rt ♥s s ♣rè st ♥ ①♣t♦♥ à ♣rés♥ ♣t ♦sré ♥s s ♥s q s ♣♥♥t sss s ♥trs F t F+ ♦♠♠♥♥t à ♦♠♥r tr♥s♣♦rt t ré♠ ♣rsst sq sss tt t♠♣értr s♥trs F+∗ ♦♠♠♥♥t à tr tr♥s♣♦rt rést♥t ♥ ♥ ♠♥t♦♥ r♣ résst♥ t ♣s ♠♣t s ♥trs F+∗ ♥st ♣s ♠ê♠♥s étt P t P ♦ù ♥ ér♥ ♥s tr rrèr ♥s s ①♦♥rt♦♥s

♦s ♦♥s é♠♥t ♦t♥ s réstts ♥térss♥ts ♥s s s♣♦sts ♣♦ssé♥t s rrèrs r3 s ♦♥t♦♥s ♦2r3♦2 ♦♥t étérqés ♣r P ♥ étr ♠♣t t♠♣értr é♣ôt sr ♥tr ♦2 strtr à été rqé ♥ étr♦ ♥érr é♣♦séà t♥s q rrèr à été é♣♦sé à ♦ ♥♦♠♠é é♥t♦♥ ss t t rs♣t♠♥t ♦ s♣érr à été é♣♦séà s ① é♥t♦♥s ♦♥t été rtérsés t ♣♦ssè♥t ♥ ♦♥♥ strtr rst♥ s ♠srs à t♠♣értr ♠♥t ♦♥t été tés t♠♦♥tr♥t ♥ rt♦r♥♠♥t ♥t ♠♥tt♦♥ s étr♦s ♦♥ r♠rq é♠♥t q ♠♣ ♦rt st s♣érr ♣♦r é♥t♦♥ t qsèr q é♣ôt à t♠♣értr éé ♠♥t t① ♦①②t♦♥ ♥tr ♦2

tt ♦①②t♦♥ rt ♦r ♥ ♠♣t ♥ét sr tr♥s♣♦rt ♦ér♥t à trrs rrèr t t rt ♠♥r ♦rt♠♥t rt♦ ♠♥ét♦résst♥ à été ♦♥r♠é ♥ ♠sr♥t s ♦rs sr s ① é♥t♦♥s ♦sré st ♣♦r é♥t♦♥ ♦ t ♥ ♥ ♣ ètr ♦sré♣♦r é♥t♦♥ t tt ér♥ ♣t s①♣qr ♥s tr♥s♣♦rtt♥♥ st ♦♠♥é ♣s s s②♠étrs étr♦♥q ∆2 t ∆5 à trrs ♥s s étr♦s ♦♠♣♦sés r strtr ♥ ♣♦r s s②♠étrs ♦♣é♥r r♠ ♣♦r s s♣♥s ♠♦rtrs t ♠♥♦rtrs ♦♥ tr rst tr ♣rt ♥s ♦t s ♥s ∆2 ♥ ∆5 ①st♥t s♠♥t ♣♦rs s♣♥s ♠♥♦rtrs t s♦♥t ♦♥ t♦t♠♥t ♣♦rsé à é♥r r♠ q♣r♠t ♦t♥r s rt♦s ♠♣♦rt♥ts P♦r ♦t♥r tt ♣♦rst♦♥ tq ♦ ç♦ s♦t ss③ r ♥ ♦t q ♣t ♥ ♣s ètr s ♥s ♥♦sé♥t♦♥s ♦ù rt♦ ❯♥ tr tr ♣t ètr strtr rrèr à ♥tr rrèr ♦♥sst ♥ ♥ sss♦♥ tr♥é ♦ r t 2 ♥ q s ①♣ér♥s ♦♥t ♦♥r♠é ♥ strtr rrèr♦rrt s ♠rs t♦♠qs à ♥tr s♦♥t ①trè♠♠♥t à étrt s♥ ♣t é♣♥r ♦ tr♠♥s♦♥ rrèr ♥s s②stè♠ été ♦ à ♥tr ♣t ♦♥sstr ♥ ♥ ♠é♥ r t 2 ♦♥t ♣♦rst♦♥ ♦♠♥é ♣♦st t ♥ét rést ♥♥ rt♦ ss③

rs♦♥ ♣♦r q ♥ ♥st ♦sré ♣♦r é♥t♦♥

Page 18: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♣♦rrt été t♠♣értr é♣♦st♦♥ ♠è♠ t ♣rss♦♥ ♥s ♠r é♣ôt ♠♥t ♥ ♦rr r♥r q ♣t ♦♥t♠♥r sr ç♦ tt ②♣♦tès st ♦rr♦♦ré ♣r r ♠♣ ♦rt♣s éé ♣♦r s é♥t♦♥s P♦r ♦♥r♠r tt ②♣♦tès ♦♥ ♣rés♥t s♦rs ❱ ♣♦r q é♥t♦♥ à ♣rtr sqs s trs rrèr àq ♥tr à été ①trt ❯♥ tr rrèr s♣érr ❱ ♣♦rs ① é♥t♦♥s ♥s ♦♥t ♦t♥ q ♦rrs♣♦♥ ♥ t q s♥trs ♦♥t été é♣♦sés ♥s s ♠è♠ ♦♥t♦♥s ①♣ér♠♥ts tr ♣rt♥ tr rrèr ❱ ❱ à été ♦t♥ ♥tr ♥érr♣♦r t ss ♠♦♥tr ♠♣t ♦①②t♦♥ étr♦♥érr q st ♣s ♠♣♦rt♥t ♣♦r é♥t♦♥ t t q ér♦ît ♣s r♣♠♥t ♦rsq s étr♦♥s s♦♥t ♥tés à ♣rtr étr♦s♣érr ♠♦♥tr q ♥tr s♣érr s♦t♥t ss ②♣♦tès ♥ étt♦①②t♦♥ ♣s ♥é étr♦ ♥érr

♥②s s réstts sèr q ♠é♦rt♦♥ s ♣r♦♣rétés s ♦♥t♦♥s♣t ètr ♦t♥ ① ç♦♥s ér♥ts ♥ ♦♥trô♥t tr♠♥s♦♥ rrèr ♦♥ ♣t ssrr r♥èr ♦ à ♥tr t ♥s é♠♥r sér♥ts trs s②♠étr ♦♥t ♦♥trt♦♥ ♦♠♥é rést ♥ ♥ r ♠♣r rrèr 2 ♣t é♠♥t ♦trà s réstts ♥térss♥ts ♥srt♦♥ ♦t à ♥tr ♣t ♥♦♥ s♠♥t♣r♠ttr étr ♦r♠t♦♥ ♦①② à ♥tr ♠s ss ♠♥tr tr s②♠étr r s étts ∆2 ♥ ∆5 ♥ s♦♥t ♣rés♥ts q ♣♦r ♥ ♣♦♣t♦♥ s♣♥ à é♥r r♠ ♥s ♦t

♥ ♦♥s♦♥ s tr① ♦♥t ♠♦♥tré ♦♠♠♥t ♣rés♥ éts ♥s rrèr ♣t ♥♥r s ♣r♦♣rétés ♠♥étqs t ♠♥ét♦ tr♥s♣♦rt s s♣♦sts ♦s ♠♦♥tr♦♥s ♥♦t♠♠♥t ♦♠♠♥t ♦♥trôr ♥tr t ♥sté s éts s♥ ♦s t ♦♥s sté ♠♣t s éts sr s trs rrèr étrq ♦s éts sr s ♥tér♥t s rrèrs â s ♦①②s ♠ét① tr♥st♦♥ ♠♦♥tr♥t té ♠îtrsr ré ♦①②t♦♥ s étr♦s rr♦♠♥étqs â s ♠ét① tr♥st♦♥ q ♦♠♣♦s♥t s

Page 19: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue
Page 20: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue
Page 21: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♥tr♦t♦♥

♦tt♦♥

♥ s♦r② ♦ t tr♦♥ ♥ ssq♥t② ts ♣rt ♣♣t♦♥ ♥ t s♥t ♥ ♥♥r♥ ♦ t ♥♦②s tr♦♥s t s♣♥ ♦ ttr♦♥ s ♦r ♦♥ t♠ ♥t ♥ ♦♥t①t ♦ ♣rt s tr♦♥ssrs ♠♥t② r② ♦♥ t♦ ♦♣ t ♥ st♦♥s♥ s♣ ♦♠♣rt♦ ♣r♦r ♦♣♠♥t ♦s② ♦♠♣tr③t♦♥ ♦rts t t② ♦ ♣r♦r♠♥♠♦st ♦ t♦♥s ♦♥ ♣♦♣ t♦ ♣r♦r♠ tss ♠♦r ♥t② ♥ ♥trst♥② t♦ rt t t♥♦♦ ♥♠♥t ♥ ♠♦r ♦ ♥t♦r♦s ♠♥t② t♦ ss ♥ sr ♥♦r♠t♦♥ ♠♦st t♦t ♥② ♣②s ♦rrs ♥ ts ♣r♦ss s st ①♣♥♥ s③ ♦ s♥ tr♥sst♦r ts ts ♣♦r♦♥s♠♣t♦♥ ♥ t♠ ♥tr rqr t♥ ♦♥st ♥♠r ♦♣rt♦♥s ssr♥♥ ②r ② ②r ♥ t ②♣♦tss rs ♥ ② ♦r♦♥ ♦♦r❬❪ ♣rt tt t ♥♠r ♦ tr♥sst♦rs tt ♥ ♣ ♦♥ ♥ ♥trt rt ♦ ♦ ♣♣r♦①♠t② r② t♥ ♠♦♥ts s ♣♣s t♦t rt♦ t♥ ♦♠♣t♥ s♣ ♥ t ♣r s s ②♣♦tss s st t♦ t s s♦② ♣♣r♦♥ s ♦ ss s ♦ ♣②ss♠② ♥♦t ♥②♠♦r ♥ q♥t♠ ts strt t♦ ♦r ♥ ♦tr ♦rs ts ♥♦t ♣♦ss t♦ ♠♥tr③ ♠♥ts ♥ss② t rt♥ ♠♦♠♥t ♦♥ s t♦strt ♦♦♥ ♦r tr♥t ♠♥s ♦ ♥ ttr ♣r♦r♠♥s ♣♥tr♦♥ss ♦♥ ♦ s rsr s

♣♥tr♦♥s s♣♥tr♦♥s s ♦ ♣②ss ♥ tr♦♥s tt♥♦♠♣sss ♠t♣ st sts ♦r t♥ ♥t ♦ t t ttt tr♦♥ s ♥ ♥tr♥ ♥r ♠♦♠♥t♠ s♣♥ t tt ♥ ♣rs♥♦ ♠♥t tr♦♥s t r♥t s♣♥s ♠② r♥t② ♥ r ♠♣t ♦♥ t ♦r ♦ ♣r♦t♦t②♣ ♦r ♥ ♦♠♠r s ts♦r♥ sr trs s♦rtr rs♣♦♥s t♠ str s♣s ♠♦r rr♦rrt ♣r♦ss♥ ♦r r ♣t②

♥ ♥ t s ♦sr s♣rt② ② r♥r ♥ rt ❬ ❪ ②s♦r tt ♥ rr♥t ♦s tr♦ t♥ strtr ♦♥sst♥ ♦ ♥♦♥♠♥t ♦♣♣r s♥ t♥ t♦ rr♦♠♥t r♦♥ ②rs trsst♥ ♦ t s②st♠ ♥s ② ♣r♥ts ♥ ♥ ①tr♥ ♠♥t

Page 22: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

sts t rt ♦r♥tt♦♥ ♦ ♠♥t③t♦♥ ♦ t tr♦s r♦♠ ♣r Pt♦ ♥t♣r P s r♥ ♥ t rsst♥ t♥ t P ♥ P♦♥rt♦♥s s ♥♦②s ♥t ♥t♦rsst♥

♦ t ♦s rsst stt ♦ tr ② ♣♣②♥ ♥①tr♥ ♠♥t s♠ t♦ r② ♣r♦♠s♥ ♥ t t s r②♥ ♣♣ ♥ r s r s ♥rs♥ tr st♦r ② ♦r ♦♥ ♦rr ♦♠♥t ❬❪ s♠ t s s♦ ♣♣ t♦ ♠♥② ♠♥t s♥s♦rs

tr♦♥s s♣♥ ♠② s♦ ♥♥ ♣r♦♣rts ♦ ♥ t ♠t②r s r♣ ② ♥ trt♥ ♥st♦r s t ♠♥tt♥♥ ♥t♦♥ ②♦♥ ♥t ♣r♦♦♦♦♥♣t ①♣r♠♥ts ♥ t s ❬❪ ♦♦r t r♣♦rt t ♦srt♦♥ ♦ s♣♥♣♦r③ t♥♥♥ r♦ss ♥♠♦r♣♦s 23 rrr t r♦♦♠ t♠♣rtr ❬❪ ♥trst♥② t t♥♥♥♠♥t♦rsst♥ ♠♣t ♦ ts ♥ s t s ♠r t♥ tt t②♣ ♦ s②st♠s ss t♥ t ♥ ts rstr♦♥ ♣♣t ♥trst

♦s rsts t♦ ♣r♦♠s♥ r st ♠t rt♦ ♦t♥r♦♠ t strtrs t ♠♦r♣♦s s♣rs ♥r ① t t r♦♦♠ t♠♣rtr ❬❪ t♦♥s ♣r♦r♠ ♥ ② r♥ t ♦♥ strtrs t❩♥ s♠♦♥t♥ rrr s♦ tt ♣t① s②st♠s ♦ ② r s t♦ tr s♣ tr♥ ♠♥s♠s ❬❪ ♥ t t♦rt t♦♥s② t♦♥ ♥ ❯♠rs ♣rt ♣ t♦ ♦r r②st♥ sstrtrs ❬❪ s♦rt② ♦♦ ② rst rsts ♦ ♦♥ t ❬❪ P♦♣♦ t ❬❪♥ ❨s t ❬❪ s s ♣♦ss t♦ ♦r♥t s②♠♠tr②♣rsr♥t♥♥♥ ♦ tr♦♥s tr♦ t r②st♥ rrr

♦r ♥ s s ♦t♥ ♦r t s②st♠s t t s♣rs s♥ t♥ t ♦r ♦ tr♦s t stst♦r② ♦♥♦t ♦ t♦s strtrs t♦ s ♦r ♣rt ♣♣t♦♥s s s t♦t ♣rt ♣♣t♦♥s rqr♠♥ts ♦r t ♠♥t③t♦♥ ♦ ♦♥ ♦ ttr♦s ♥s t♦ ♣♥♥ ts r♠♥ ① ♥ s♣ t ♠♥t③t♦♥♦ t r ②r s st t♥ ♣r ♥ ♥t♣r ❬❪ ♥str② s♣♥t♠♦r t♥ t♦ rt strtr ♦ ts t②♣ t♦t ♥② str♥ s s♦t♦♥ ♥♦r♣♦rts ♦ tr♦s ②s t s♥ ♣ t♦ t t r♦♦♠ t♠♣rtr ❬❪ s sss r ♣rs♥t t♥ ♦t t♦rt♥ t ①♣r♠♥t ♣rt ♦ ts tss

♦ rtr t ♥s t ♦ s♣♥tr♦♥s ② rqrs s♦r ♦ tr♦♥stt s ② s♣♥♣♦r③ ♦♠♣ss ts tr♦ t tr♥ ♦♣♣r♦♣rt tr♦♥ s②♠♠trs ♥ t ♦rs ♦ t s♦stt t♥♥♥ ♣r♦ss♥♦tr ♣t s t♦ s rr♦♠♥ts tt ♣r♦ tr♦♥ ♦♥t♦♥ ♦♥② ♦ ♦♥s♣♥ t②♣ s ss ♦ ♠trs s ♠ts ②♦♥ ♥t ♦srt♦♥s❬❪ ♥trt♦♥ t♥ t♥♥ ♥t♦♥s t♦ t ♦srt♦♥ ♦ ♦r rt♦ ❬❪ ♣r♦♠ rs♥ r♦♠ s♥ ♠ts s tt tr ♦tst♥♥♣r♦♣rts ♥ ♥trt ♥t♦ ♠♥t t♥♥ ♥t♦♥s ♥s ♦ t r

Page 23: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

t♠♣rtr ♦ t ♥t♦♥ ♥tr s ♦ t r♦♦♠ t♠♣rtr t♦ t ♥tr ♠♦t♦♥ ♦ t tr♦♥ strtr s s t s♦r t ♠♦st ♦♠♠♦♥② st ♠t t 0.7r0.3♥3 ❬❪

♦r ♦ t ♦r♠♥t♦♥ ♠♥t t♥♥ ♥t♦♥ s②st♠s ♣r♦♠ sr ② r②st♥ strtrs ♥♠② ts ❱r♦s s♦t♦♥s ♥♥s ♥ t t♦♠ ♥t♦r ♥ str♦♥② t t rrr ♣r♦♣rts ♥♥st♦rs tr ♥tr♥s ♥ ♣ ♠② t t stts t ♥rs②♥ t♥ t t♦♣ ♦ t ♥ ♥ ♥ t ♦tt♦♠ ♦ t ♦♥t♦♥ ♥r ♣rs♥ t② rs t rrr t ♥ ts t ♦r♥t tr♥s♣♦rt ♦ tr♦♥s ② ♣r♦♠♦t♥ ♦♣♣♥ r♠ ♦ tr♥s♣♦rt s ♣rs♥t♥tr ♦①t♦♥ ssttt♦♥ ♦ sts t♥ stts t♦♠ s♦♥ ♥♥rt♥ tr♠♥t♦♥ ♦ ♦t rrr ♦r tr♦ ②rs ♥ s♦ str♦♥② t ts♣♥♣♦r③ tr♥s♣♦rt

♥ t② t♦ ♦♥tr♦ t ts r♥ t rt♦♥ ♥ ♠♦♥t♦r trtt② r♥ t t♥♥♥ ♣r♦ss ♦ s♥ ♥ t♦♥ t t tr r♦♥ t s♣♥♣♦r③ tr♥s♣♦rt ♦♥rr♥t② t ♣♦sst② t♦ rt s♣ t②♣s♦ ts ts ♦ ♦ t♦ ss② tr ♣r♦♣rts ♥ ♣♦t♥t② ♠ ♥ s♦ t♠ ♥ ♦rr t♦ rtr ♥♥ ♣r♦♣rts ♦ ♠♥t t♥♥ ♥t♦♥s ♥t♦ s♣ ♣♣t♦♥s ♠♠rst♦rs ♥ ts s ♥s r r♥ ②t rr♥t ♦ rsts ♥ trt♦♥ ♦ t tr♦♥ tr♥s♣♦rt ♣r♦♣rts t t sts ♥ ♦♥sq♥t② ♥ t rsst♥ ♦ t s②st♠ ❬❪

trt rsr s ② ♥♦ t♦ r ♦r ♥rst♥♥t ♣r♦r♠♥ ♦ s s ♦♥ s♠♦♥t♥ ♠trs s♦♥ r♠♥♠ ♦r ♠ rs♥ ♦r t s♠ ♦ ts ♦♥tr♦ ♦s ♥♦t ①st♦r ♦① trs ♥ t♦ t② r ♦♥sr t s ♦r tr s♣♥tr♦♥♥ ♠♠rst ♠trs ♠ ♦ ts tss s t♦ sts ♣r♦sss tt t♦ t t ♦♥tr♦ ♥ ♠♥t t♥♥ ♥t♦♥s s ♦♥ r3 ♥ 2

rrrs ❲ sr t r♦t rtr③t♦♥ ♥t♦♥ ♣ttr♥♥ ♥♠♥t♦tr♥s♣♦rt rsts ♦♥ sts ♥ ♦s ♦♥ t ♥tr ♦ t stts♥ tr r♦ ♦♥ s♣♥♣♦r③ tr♥s♣♦rt

Page 24: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♥sr♣t r♥③t♦♥

rst ♣rt ♦ t tss ♦rt ss s ♥ t♦ ♣trs♥ t rst ♦♥ ss ♦ t s♣♥♣♦r③ tr♥s♣♦rt r ①♣♥ ❲t♥ trst tr st♦♥s strt♥ r♦♠ t s♠♣ s ♦ t s♣♥♥♣♥♥t tr♦♥tr♥s♣♦rt tr♦ t ♣♦t♥t rrr t s♣♥♣♥♥t ♣tr s ♦♥st②♥tr♦ r ♠♦ t ♠♦rt② ♥ ♠♥♦rt② tr♦♥ s♣♥ ♣♦♣t♦♥s♥ t ♦ ♥st② ♦ stts ♦♥♣t ♥ tr♦s r ①♣♥ ♥ st♦♥ t ♠♣t ♦ ♦ s②♠♠trs ♦♥ t t♥♥ ♠♥t♦rsst♥ s s♦♥ s♥t ①♠♣ ♦ t ♠♦ s②st♠ s t s ♥rst♦♦ ♥ s ♣♦ ①♠♣ t♦♥ srs r♥s ♥ s♣♥♣♦r③ tr♥s♣♦rtr♦ss ♥ r32 r②st♥ rrrs s①t st♦♥ ♥tr♦s♥t♦♥s t r♦♥ tr♦s r♣ ② ♦ ♦ ♦ ♥ 0.7r0.3♥3t s♣ tt♥t♦♥ ♥ t♦ t st t♦ s s t♦ t♦ ts s♥♥t ♣rt ♦ ts tss ♦♥r♥s s ♥♦r♣♦rt♥ ♦ tr♦s ♥ ♠t s ♥ ♥trst♥ ♥t ♦r t tr♦ ♠tr ♥ ♠♥tt♥♥ ♥t♦♥s s♦ rt♦♥ ♦ s s ♦♥ ts ♦♠♣♦♥ s s♦ tt♠♣tr♥ ts tss t♦♥ ♥tr♦s t s②st♠ ♦♥ t st s♥ s ♦sr ♣ t♦ t

s♦♥ ♣tr ♦ t t♦rt ♣rt srs t ♠♣t ♦ ts ♥ r②st♥ s②st♠s ♦♥ s♣♥♣♦r③ tr♥s♣♦rt rst st♦♥ ♦♥♥trts ♦♥ tsts ♣rs♥t t♥ tr r②sts ♥ ♦ t② ♠② ♦♣t② ♥ tr②♣r♦ rs t s♦♥ st♦♥ srs t ♦r♥s ♥ ♦♥sq♥s ♦ ♠♣rt♦♥s ♣rs♥t t ♠t♥st♦r ♥trs tr st♦♥ ssss sss♦ tr♦♠rt♦♥ ♥ ♣rs♥ts t ♣♥♦♠♥♦♥ s t♦♦ t ♠♥tt♥♥ ♥t♦♥s ♠② ♥♥r ♥ ♦rr t♦ tr tr tr♥s♣♦rt ♣r♦♣rts ♦rt st♦♥ ♥tr♦s t♥ ♠♥ts♠ ♥ tr ♥st♦rs ♥ ts♣r♦♠s♥ ♣♦ssts ♦ tr t♥♦♦ ♣♣t♦♥s

s♦♥ ♣rt ①♣r♠♥t r③t♦♥ srs q♣♠♥t ♠trs ♥♣r♦rs s ♦r rt♦♥ ♣r♦ss♥ ♥ ♠sr♠♥ts ♦ strtrs stt♥ t t♠r♠ ♦ ts tss rst ♣tr ♦ ts s♦♥ ♣rt r②♥tr♦s sr ❯❱ ♣♠♣♥ s②st♠s t s♦♥ ♦♥ ssss t ♣r♦r ♦ sstrt ♣r♣rt♦♥ ♦r t s♣ttr♥ ♣♦st♦♥ s ♣r♦r♠ ②♦r r♦♣ ♥ ♠s r♦t t♥qs ♥ ♣r♦rs ♦ s♣ttr♥ ♣♦rt♦♥♥ ♣s sr ♣♦st♦♥ r ♣rs♥t ♥ st♦♥s t♦ rs♣t② ❱r♦sqt② ♦♥tr♦ s②st♠s ♦r ♦t rt♦♥ ♥ ♣r♦ss♥ r s♦ ♣rs♥t st ♥tr ♦ ts tss s ♠♦st② ①♣r♠♥t ♥ ♦t t rt♦♥ ♦ s♠♣s ♥ tr ♣r♦ss♥ t♥q ♦♣♠♥t r ts ss♥t tss ♠♥② ♦①♣r♠♥t rsts s s tt♠♣ts r ♣rs♥t ♥ ts st♦♥

s♦♥ ♣tr ♦ t s♦♥ ♣rt ♣tr srs ♣r♦rs t♦ ♦♥rt♥tr ♠t②rs ♥t♦ ♠sr s ts rst st♦♥ srs ♥ ♥ sts♦♠s ♣ttr♥♥ t♥q ♥tr♦ t♥ ♦r s♣ttr♥ s②st♠ r♥

Page 25: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

t t♠r♠ ♦ ts tss t s ♦♦ ② ♦♥ st♦♥ tt srs ♣r♥♣s♦ ♠tst♣ ♦♣t t♦r♣② ♦rt st♦♥s t♦ sss ♥t ♣r♦♥ ♦ t♣r♦ss s ♣rs tt♥ sss ♥ t ♥ ♦♥♣ ♠♦♥t ♥ t r♦♥♥ rs♣t②

tr ♣tr ♦ t s♦♥ ♣rt ♣tr ♥tr♦s ♦r t♥qs t♦♠sr s ♣ts ♦ t st♦♠♠ st♣ ♦♥ ♠♦st♦ rt ①♣r♠♥ts r ♣r♦r♠ r ♣rs♥t ♥ st♦♥ s♦♥ st♦♥ ♣rs♥ts ①♣r♠♥t t♥qs ♦ t rrr t tr♠♥t♦♥ tr st♦♥ ♣rs♥ts ♣r♦♣rts ♦ ♦♣t st♣s t s♦r♣t♦♥ ♥♣♦t♦♠♥s♥ s♣tr ♣rs♥t ♥ t ♠♥sr♣t r ♦t♥

tr ♣rt st② ♣rs♥ts rsts ♦t♥ ♦♥ tr r②sts♥ ♠♥t t♥♥ ♥t♦♥s st t♥ t t♠r♠ ♦ ts tss rstt♦ st♦♥s ♦ t rst ♣tr ♣tr sr rsts rt t♦ r3 ♥2 tr r②sts ♥ s s ♦♥ ts ♠trs tr st♦♥♣rs♥ts tt♠♣ts t♦ ♠♣r♦ ♣r♦♣rts ♦ ts ♠♥t t♥♥ ♥t♦♥s ② r♣♥ tr tr♥st♦♥ ♠t tr♦s t 0.7r0.3♥3 s♦♥ ♣tr♣tr ssss rsts ♦ ①♣r♠♥ts ♣r♦r♠ ♦♥ rrrs st♦♥ ♥ ♠♥t t♥♥ ♥t♦♥s ♥ t rrr s s♥ t♥t♦ t②♣s ♦ tr♦s t s②st♠s rt t t s♦♠st♥q st♦♥ ♥ t ♦♦ s ♦♥ ①♣r♠♥tsr ♣r♦r♠ ♥ t ♥ ♠♦♥ts ♦ ts tss st♦♥ ttr st♦♥s ♣rtr② ♦♥ t♦ t t ♥②ss ♦ t ♦t ♥ t♠♣rtr♣♥♥ ♦ t s♣♥♣♦r③ ♦♥t♥

♦rt ♥ t ♥ ♣rt ♦♥s♦♥s ♥ ♣rs♣ts s ♥ t♦♣trs t s♠♠r② ♥ t r♦♠♣ rst ♦♥ r② rs ①♣r♠♥ts♥ rsts ♦t♥ ♦♥ ♦t t②♣s ♦ s tr♥st♦♥ ♠t ♦①s ♥ r♥ ts tss ♥ s♣rt st♦♥s s♦♥ ♦♥ ♣rs♥ts ♣♦t♥t s♦t♦♥s ♦rt♦♥ ♣r♦ss♥ ♥ tr♥s♣♦rt sss ♥♦♥tr r♥ t t♠r♠ ♦ tstss ♦r♦r ♣r♦♣♦st♦♥s ♦ rtr ①♣r♠♥ts tt ♦ s♥ t♦♥t ♦♥ ♠♣t ♦ strtr ts ♦♥ s♣♥♣♦r③ tr♥s♣♦rt r ♣rs♥t

Page 26: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue
Page 27: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

Prt

♦rt ss

Page 28: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue
Page 29: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♣tr

ss ♦ ♥♥ ♥t♦rsst♥

rst st♦♥ ♦ ts ♣tr srs t ② tr♦♥s t♥♥ r♦ss t ♣♦t♥t rrr s♦♥ ♦♥ ①♣♥s ♦r♥s ♦ t ♥♦♥③r♦ s♣♥ ♣♦r③t♦♥ ♥rr♦♠♥ts tr ♦♥ ss t ♥♦r♠t♦♥ r♦♠ t ♦r♠r t♦ ♣rs♥t♥ s②st♠ ♦♠♣♦s ♦ ♥ ♥st♦r s♥ t♥ t♦ rr♦♠♥ts ♥ t rr♥t ♦ s s♣♥♣♦r③ ♣r♥♣ ♦ ♦♣rt♦♥ ♦ ts s②st♠ ♥t ♥♥ ♥t♦♥ s ♣rs♥t ♥ t ♦rt st♦♥ s ♦♥ t ①♠♣♦ t s②st♠ ♥♥ ♦ tr♦♥ ♦ ♥t♦♥s rs♥r♦♠ t ♥ strtr ♦ t ♠trs s sss ♥ t♦rt t♦♥s♦ tr♥s♣♦rt ♥ ♥tr♥s trs ♦r♥ t r ♣rs♥t t st♦♥♣rs♥ts ♣r♦♣rts ♦ t♦ r②st♥ rrrs r♥t t♥ ♥♠② r3

♥ 2 s①t ♦♥ ♥tr♦s sr r♥t tr♦ ♠trs ♥ srs ② ♦ tr♦s r ♦ ♥trst ♥ tr♠s ♦ ♣rt ♣♣t♦♥s s s sss rt t♦ ♦s s ♥ r♥s r♦♠ t ♥ tr♠s ♦ s♣♥♣♦r③ tr♥s♣♦rt 0.7r0.3♥3 tr♦s r s♦ ♣rs♥t♥ ts st♦♥ t ♠♥s♠ ♦ ♦ ①♥ ♥ rs t♦ t ♠t ♦r ♥ tr♥s♣♦rt ♣r♥♣s ♦ t tr♦ s ♣rs♥t st st♦♥ ♦ ts ♣tr ♣rs♥ts t ♠♥t t♥♥ ♥t♦♥ ♦♥ t st ♣ t♦ t s ♦sr t s②st♠

r♦♠ s♠♣ t♦ ♣t① rrrs

t ♠② s♠ ♠♣♦ss r♦♠ t ss ♣♦♥t ♦ tt ♦♥ ♠② s♠♣② tr♦ ♦r t♦ t ♣rt t② ♦ ♠ttr ts t♥sr ♣♦ss ♥ ♥♥♦s s②st♠s ♦r q♥t♠ s ♦ ♣②ss ♣♣② sstrt ♦♥ ♦♥ ♠♥s ♥ tr♦♥ t ♥r② ♥ t♦r ♣♣r♦♥ s♠♣ rrr t ♣♦t♥t ❱ tr s ♥t ♣r♦t② tt t ♣♥trt tr♦ t rrr t ts ♠♣t tt♥t ①♣♦♥♥t② tt rrr t♥ss ♥ ts ② ♣r♠tr κ = (2m/h)(V − E) r V > E❬❪

Page 30: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯

r ♠t ♣tr ♦ ♥ tr♦♥ t♥♥♥ tr♦ s♠♣ rrr rst♥ ♦♥t♥ s rt t♦ t ♥s♥t stt ♦ t tr♦♥ ♥ ts② ♣r♠tr t♥ t ♥st♦r t rrr s t♥ ♥♦ s♦ ts ♠♣t♦s ♥♦t t♦ ③r♦ t tr♦♥ ♠② r t ♦tr s t t ♣r♦t② ♦ ts♥t♦♥ ♠♥s ❬❪

s♣t rt♥ ①♣r♠♥ts tt ♥♦ ♠ rrrs ♥♦♥♦♥tt ♠♦♦ s♥♥♥ tr♦♥ ♠r♦♦♣② ts tss s t t♥♠ s②st♠s ♥ t rrr s ♦♠♣♦s ♦ t♦♠s rrrs ♥ ts t♦♠s r ♦rr r ♦s♣ ♥trst ♦ ts st② ♥ s r②st♥ s t ♦ ♦♥t♦♥ ♦r stts♣r♦♣t♥ r♦♠ st r t♦ ♥♦r♥ st r + ♠② rtt♥ s Ψk(r + ) =cΨk(r) r c = exp(i · )

♦ qt♦♥ srs ♠♦t♦♥ ♥ ♣r♦ ♣♦t♥t t t♦r s r q♥tt② ♦r tr♦♥ ♠♦t♦♥ ♥ ♠t t s ♠♥r②♥ t tr♦♥ trrss s♠♦♥t♦r tr♦ t t♥♥♥ ♣r♦ss ♥ tts t ♥t♦♥ ②s ①♣♦♥♥t② s t tr♦♥ ♣r♦♣ts tr♦ t♦♥ ②r tr♦♥ stt s t♥ ♥s♥t

❲♥ ♥ tr s s ♣♣ t♦ t strtr t ♥r② s r r♥ ♦t♦ t qr♠ s s s♠t② s♦♥ ♦♥ ♠♠♦♥s ♣r♦r♠ t♦rt t♦♥s ♦♥ rr♥t ♦♥ r♦ss ♣♦t♥t rrrs ♥r r♥t s♦ts ♥ sts ♥♦♥ qt♦♥s ♦ tr♦♥ t♥♥♥ tr♦ ♥r③ rrrs ❬❪ s ♠♦ s rtr ①t♥ ② r♥♠♥ ♦ ♣rt t♣♥♦♠♥ ♦r s②♠♠tr rrrs ② ♥ ∆φ = φright − φleft ♣r♠tr ❬❪s ①♣t t ♠♦♥t ♦ rr♥t t♥♥♥ tr♦ ♣♦t♥t rrr ♥rsst t ♣♣ s t r ♥ V = φ0/e ♥ ♦rr t♦ tr♠♥♣r♠trs ♦ ♥ ♥♥♦♥ rrr ♦♥ ♠② t ts rr♥t♦t rtrsts t

Page 31: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P❳

r ♠t ♥r② r♠ ♦r rrr ♥r t s ❱ ♣♣ ♦rt ♥ r rt t♥ t rrr t φ0 ♦t tt ♥ t ttr s ♥♦t♦♥② t rrr t s r t ts t t♥ss ∆s s

♦r ♥ r s ♦r♥ t♦ t ♠♦ ♦ r♥♠♥ ♦r ts ♠♦st srs r♦♠ s♥ts rst♥ r♦♠ t ♦♠ss♦♥ ♦ rt♥ ts t③r♦ s ♥♦♠② st♦♥ ❲♥r ♣♦ss ♥ ①♣r♠♥t ♣r♦r I s s ♥ ♦rr t♦ tr♠♥ t rrr ts s st♦♥

r ♦r ♠♦st t♥♥♥ s②st♠s t tr♦♥ tr♥s♠ss♦♥ ♣r♦t② s♥♣♥♥t ♦ ts s♣♥ ♦r♥tt♦♥ r t s♣♥ ♣♦r③t♦♥ qs ③r♦ ♦♥ ♦tss ♦ t rrr ❬❪

♥ ♠♦st ♦ r s②st♠s t rr♥t ♦ ♠♥s ♥♦t ♦♥② ♦♥ t r ♥♠r♦ tr♦♥s tr♦♥ s r♠♦♥ s ts s♣♥ ♦ h s ♥ ♣♦st ♦r ♥t s♣♥♣ ↑ ♦r s♣♥♦♥ ↓ rs♣t②♦r ♥♦♥♠♥t ♠trs t ♠♦♥t ♦ s♣♥ ♣ ♥ s♣♥ ♦♥ tr♦♥s s ts♠ ♥ ♦♥ ♠② s② t s♣♥ ♣♦r③t♦♥ qs ③r♦ ♥ s s ♥♦ tr♥s♣♦rt♣r♦♣rts ♣♥ ♦♥ t s♣♥ s s♣♥ ♣♦r③t♦♥ ♥ ♠tr

Page 32: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯

♠② sr t t qt♦♥ ♦ ♥ ♥♠r ♦ t tr♦♥s t tr♠ t rs♣t ↑ ♦r ↓ s♣♥s

P =N↑ −N↓

N↑ +N↓

♦♥③r♦ s♣♥ ♣♦r③t♦♥ ♥ rr♦♠♥ts

r ①♥ s♣tt♥ ♦ s♣♥ ♥st② ♦ stts ♦r t♦ t①♥ s♣tt♥ ♦ s♣♥ s♥s t t t r♠ s r♥t ♦r s♣♥↑ ♥ s♣♥ ↓ ♣♦♣t♦♥s t♦♣ ♥ ♦tt♦♠ ♣rts rs♣t② ❬❪

tr♦♥ ♣r♦♣rts ♦ ♠trs ♥ r♣rs♥t ② tr ♥ strtr❲♥ r ♦r s♣ t ♥r② ♣♥♥ ♦ t ♥ strtr ②s t♠trs ♥r②♣♥♥t ♥st② ♦ stts ♦♥t♥ ♥ ♠tss ♦♦s② rr ♦t ② t tr♦♥s ②♥ t t r♠ F ♦r r② ♦st♦ t s ♥♦t ♦r ♦r ♥♦♥♠♥t ♠trs t strt♦♥ s q♦r ♦t s♣♥ ♣♦♣t♦♥s s♦ t s♣♥ ♣♦r③t♦♥ ♥ ♥t ♦r ♥♠trs tt ①t rr♦♠♥t ♣r♦♣rts tr t♦ s♣♥ s♥s r t② t ①♥ s♣tt♥ s s♦♥ ♦r t ①♠♣ ♦ r♦♥ ♦♥ s r②ts t tr♦♥ ♣♦♣t♦♥ t t r♠ ♥♠r ♦ stts t F ♦r tr♦♥s t rs♣t s♣♥s s ♥♦♥q ♥ ♦♥ ♠② t ♦t ♥♦♥③r♦ s♣♥ ♣♦r③t♦♥

t t ♠r♦s♦♣ rr♦♠♥t s rtr③ ② t s♣t ♦r♥tt♦♥♦ ts ♠♥t③t♦♥ s ♠♥t③t♦♥ rts t t tt t♦ ①♥s♣tt♥ ♦♥ s♣♥ s♥ s ♠♦r t♥ t ♦tr r ♦ ♥♣♥s ♦♥ t rr♦♠♥t ♦♥sr s ♠♣s tt ♦♥ s♣♥ ♣♦♣t♦♥

Page 33: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

PP❩ ❯ ❯ ❯

t ♠♦rt② s♣♥ ♦r s♣♥♣ ♣♦♣t♦♥ s ♠♦r ♥♠r♦s t♥ t ♦tr ♠r♦s♦♣ ♠♥t③t♦♥ ♦ t ♠tr ♥ t q♥t③t♦♥ ①s ♦ ♠♦rt② s♣♥tr♦♥s r ♥ t♦ ♥t s♣♥ q♥t③t♦♥ ①s ♦r t ♠♥♦rt②♦r s♣♥♦♥ tr♦♥s s tr♦r ♥t♣r t♦ t ♠♥t③t♦♥ ①s

♣♥♣♦r③ t♥♥♥ ♥ ♠♥t t♥♥ ♥

t♦♥s

strtr ♥ ♥♥♦♠trst ♥st♦r s s♥ t♥t♦ rr♦♠♥t tr♦s s ♥t t♥♥ ♥t♦♥ ♥qs s t♦ rt s s②st♠s r ①t♥s② ♣rs♥t ♥ t s♦♥ ♣rt♦ t ♠♥sr♣t r t ♥r ♥♦r♠t♦♥ ♦t rr♦♠♥t♥st♦rrr♦♠♥t s②st♠ s ♥

r ♦r r♥t ♠♥t③t♦♥ ♦♥rt♦♥s ♦ t rr♦♠♥t tr♦s ♥ ♠♥t t♥♥ ♥t♦♥

t ♦r s ♦ t t♦ ②rs r r♥t t♥ s ♥ ①tr♥♠♥t s r♠♣ r♦♠ ♣♦st tr♦ ③r♦ t♦ ♥t t♠♥t③t♦♥ ♦ ②r ♣ s♣rt② ♥ tt s t strtr ♠②t ♦♥ ♦ ♦r r♥t ♦♥rt♦♥s ♦ rr♦♠♥ts s s♦♥ ♦♥

♥ s♥ ♦ ♥② s②♠♠tr② r♥ ♥ ② t ①♥ s ♦ ♥ ♥trr♦♠♥t t ♣♦st ♥ ♥t rt♦♥s ♦ ♠♥t③t♦♥ ♦r ②r r q♥t ♥ ♥r② ♥ tt s t ♦r ♣rs♥t ss ♦ trt ♠♥t③t♦♥ ♦ t rr♦♠♥ts ♥ s♠♣ t♦ t♦ Pr P♥ ♥t♣r P

t t r② ♥♥♥ ♦ t s♣♥tr♦♥s t♠♥ r ♣r♦♣♦s tttr♦♥ ♦♥t♦♥ r♦ss ♠t s②st♠ s♦ ♦♥sr s ♦rr♥ ♣r♠r② t♥ t♦ s♣♥ s♥♥s ❬❪ s ♠♥s tt t t♦t ♦♥t♥ ♦t s②st♠ ♥ t P ♦r P ♦♥rt♦♥ s t s♠ ♦ t ♦rrs♣♦♥♥ ♠♥♦rt②♥ ♠♦rt② ♦♥t♦♥ ♥♥s GP = G↑↑ + G↓↓ ♥ GAP = G↑↓ + G↓↑♦r♦r ♣r♦♣♦s tt rr♥t t♥♥♥ tr♦ ♥♥ ♣r♦♣♦rt♦♥t♦ ts t t r♠ ♦r ♦t tr♦s ♥ ts tr♠s tr s♣♥ ♣♦r③t♦♥ ♥ rtt♥ s P = (D↑ −D↓)/(D↑ +D↓) ♦r t t♦rr♥t ♠♦

Page 34: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯

r ♠♣ s♣♥♦♥sr♥ t♥♥♥ r♣rs♥tt♦♥ ♦r ♦t ♣r ♥ ♥t♣r ♦♥rt♦♥ ♥♦t ♥sts ♦ stts ♦ t rs♣ttr♦s ♦t tt ♥ t P ♦♥rt♦♥ t s♣♥♣ stts ♥ t ♠♥t③t♦♥rr♥t ♦ ♦♥ tr♦ ♦♠ s♣♥♦♥ stts ♥ t ♠♥t③t♦♥ rr♥t♦ t ♦tr ♥ rs ❬❪

♥t t s♣♥♦rt ♥trt♦♥ s rtr ①t♥ ② ♦♥③s ♦rt s ♦ t♥♥♥ r♦ss ♠♥t t♥♥ ♥t♦♥s t ♥ ♠♦r♣♦s rrr❬❪ ♣♥♦♠♥ s tr sr ♥ ♠♦r t ♦r r②st♥ rrrs ②tr ♥ t♦♥ ❬ ❪ s♣♥♦♥sr♥ t♥♥♥ s s♠t② s♦♥♦♥ t s ♠♣♦rt♥t t♦ ♥♦t tt ts ♠♦s ♣♣② t♦ t ♣rt s②st♠s♥ ♦ ♥♦t t ♥t♦ ♦♥t t♦♥ ts ♣♦♣t♦♥ ♠①♥ t♦ ts♣♥♣♣♥ ♦r ♦t ①tt♦♥s ♦ s♣♥s ♥♦♥ s ♠♥♦♥s

②♠♠tr② tr♥ ♥

sst♥t ♣rt ♦ ts tss s t t♦ t s②st♠ ♣♦st t♦♣ t ♣rt ♠♦♥♦r②st r♦s r②st♥ ♦r r♦tt ②

s t tt ♦♥st♥t s r♦②√2 rr t♥ tt ♦

tt ♠s♠t s r♦♥ ♣r♥t s ♥♦t ♥♦ t♦ st♦rt t r②st ❬❪ t s s♦ t♦rt② ♥rst♦♦ strtr tt ♥ sr s ♣♦ ♠♦ t♦ sr t s♣♥♣♦r③ t♥♥♥ tr♦ t ♠♥tt♥♥ ♥t♦♥s s ts st♦♥ ♣rs♥ts t ♠♣t ♦ ♦ ♥t♦♥s♥ ♥ strtrs ♦♥ t t♥♥♥♥ tr♥ ♦ tr♦♥s t ♣rtrs②♠♠tr② r♦ss t ♠♥t t♥♥ ♥t♦♥s

tr♦♥ ♦ ♥t♦♥s

♥ r②st♥ s②st♠s r ①s② st t♥ ts tss t t♦♠♥rt ♣r♦ ♣♦t♥t t ② t tr♦♥ s t trrss t tt ♣♥s♦♥ t rt♦♥ ♦ ♣r♦♣t♦♥ t♥ t tt s ♦t ♥ t rrr ♥ ♥

Page 35: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❨❨

r ♦♣ ♥ r♦ssst♦♥ ♦ t r♦♥ t♦♣ t ♠♦♥♦r②st ❱t♦rs ♦ ♥♦t r②st♥ ♦r♥tt♦♥s ♦ ♦t ♠trs ❬❪

r t♦♠ ♦rts r♦♣ ② s②♠♠tr② ♣r♦♣rts ♥ t rt♦♥ ♦♣r♦♣t♦♥ r tr♥srs ♥♦s r s♠t② r♥ ♦♥ t rt ♦ s②♠♠tr② ❬❪

t tr♦s t tr♦♥s ♥ sr t tr ♦♠♣♦♥♥ts ♦ t ♦t♦rs ♣r t♦ t ♥trs ♣r♣♥r t♦ t rt♦♥ ♦ ♣r♦♣

Page 36: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯

t♦♥ s♣ ♣ ♥ s② ∆1 ∆5 ♥∆2∆2′ rs♣t② ♣♥♥♦♥ t ♥ strtr ♦ t ♠tr tr ♠t ♦r ♥st♦r tr♦♥s t s♣ tr♥srs ♠♦s s②♠♠trs ♥r♦ tr rs♣t sttr♥ rts ♦rts rs♦♥ ♦♥ ♠② s♣ ♦t s♣ ♦♥t♦♥ ♥♥s

♥ strtrs ♠♣t

r r♦♥ ③♦♥ t s②♠♠tr② ♣♦♥ts ♥♦t Γ− s t rt♦♥ ♦ t ♣r♦♣t♦♥ ♦ tr♦♥s sr ③♦♥ s s♦r♥ ♦♥ t rt t t Γ−X rt♦♥ s♣ ❬❪

♥ ♦rr t♦ ♥rst♥ t ♠♣t ♦ tr♦ ♥ rrr ♥ strtrs ♦♥ ts♣♥tr♦♥ rs♣♦♥s ♦ t s②st♠ r♦♥ ③♦♥ ♦r s♥tr s②st♠ s ♣rs♥t ♦♥ ♥ s②st♠s tr♦♥s r♠ t♦ ♣r♦♣t ♦♥ t Γ− rt♦♥ t♥s t♦ ♥ ①tr♥ ♣♣ tr

♥s♠ ①

♥r rs♦♥ ♦r s♥ r②st♥ rrrs s tr t② t♦ ♣rsr t s②♠♠trs ♦ tr♦♥s r♥ t tr♥s♣♦rt s ♦r♥t tr♥s♣♦rt s t ♠♥♥t ♦r ♠♦r♣♦s ♥st♦rs 23 ♥ ♥tr♠①♥ ♦ s②♠♠trs t♥ t rrr rsts ♥ tr ♣♦♦r tr♥ ② t ♦t♦r ♥ t s ♦ r②st♥ rrr s♦s t s tr♦♥s ♦ s②♠♠tr② ♥r♦ tr rs♣t s②♠♠tr②♣♥♥t tt♥t♦♥ t♥t rrr

Page 37: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❨❨

r ♠t ♦♠♣rs♦♥ ♦ ♥ ♥♦r♥t t♥♥♥ tr♦ t 23

♠♦r♣♦s rrr ♥ ♦r♥t tr♥s♣♦rt tr♦ t r②st♥ ❬❪

r ♥tr ♥ ♦♠♣① ss ♥ strtr ♦ ❬❪ ♠rs♥♦t rs♣t ∆ tr♦♥ s②♠♠trs ❬❪

s ♠♥t♦♥ ♥ st♦♥ ♥t♦♥s ♦♠ ♦♠♣① ♥ t♥♥♥♦rs ♥ ♦rr t♦ ♥rst♥ t ♠♥s♠ ♦ ② t♥ t ♥st♦r ♦♥ s

Page 38: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯

t♦ ♦♦ t ts ♦♠♣① ♥ strtr s strtr t ♦r t r②st♦♥ t ♦♥trt♦♥s ♦ ts rs♣t tr♦♥ s②♠♠trs s s♦♥ ♦♥ ❬ ❪ ss♥t ♦♥♣t ♦ t ♦♠♣① ♥ strtr s t ♥tr♠t♥ ♦ ♥t♦♥s t t ♦♥r② ♦ t t♦ r②sts ♥ s ♦t ♠t♥st♦r ♥tr r ♠t♥ ♣ stts s sttsr t♥r♥t ♥ t ♠t t ② ①♣♦♥♥t② ♥ t ♥st♦r t♦ ♣rs♥♦ t ♥ ♣ ♦r♠♥ t ♦♠♣① ♥ strtr ♦ t ♥st♦r ❬❪ t♦r♠♥t♦♥ ♥s♥t stts r ② ♣r♠tr s t ② ♣r♠tr κ❬❪ ♦s s♣rs♦♥ s ♣♦tt s s ♥t♦♥ ♦ ♥r② r♦ss t ♥ ♣ ♦ ts♠♦♥t♦r ♦♠♣① ♥ ♦♥♥ts t ∆1 ♥ ♥ ♦♥t♦♥r ♥s s s♠r t♥ ♥② ♦tr ♥ t ♦s ♥♦t ①t♥ t♦rs t rs ♦ t ② ♣r♠tr κ tt rs t tr♥s♠ss♦♥ ♣r♦t② e−2κds ♠♣s tt t s t ∆1 stt tt s t ♦st ② rt s ♦r rr♥t ♥♦♠♣ss♥ s②♠♠trs tt ♠♣♥ ♦♥ t t♥♥ rrr ♠♦st♦ t rr♥t t♥♥♥ r♦ss t rrr s t② ♦ t ∆1 s②♠♠tr② ♦rt r♠ ②♥ ♥ t ♥tr ♦ t ♣ tr s ♦♥② ♦♥ ∆1 κ ♥s♥tstt tt ♦♥♥ts ♦♥t♦♥ ♥ ♥ ♥s s②♠♠tr② κ ♦ t ∆5 ♥s s♦♥ t♦ tt ♦ ∆1 ts t ②s t♥ t rrr str ∆2′ ♦♠♣①♥ ①t♥s rtr t♦rs κ s s♦ tr♦♥s ♦ t ∆2′ s②♠♠tr② ♦♥trt t♦ t t♥♥♥ rr♥t ♠ ss t♥ ts ♦ ∆1 ♥ ∆5 s②♠♠trs

♦t tt t s ♣rs♥t ♦♥r♥s t r②st ♥②ss ♦ t♦♠♣① ♥ strtr ♥s t♦ ♣r♦r♠ ♦r t②♣ ♦ t ♦① rrr ♥♦rr t♦ tr♠♥ ts tt♥t♦♥ rts ♦r s♣ s②♠♠trs s s♦♥ ♥st♦♥ ♦r rrrs r♥t t♥

r♦♥

ts t ♦♦ t t ♥ strtr ♦ t rr♦♠♥t ♦r ♦t s♣♥♣♦♣t♦♥s ♦♥ t Γ− tr♦♥ ♣r♦♣t♦♥ rt♦♥♦♥ ♥ s tt stts t rt♥ ♥t♦♥ s②♠♠trs ①st t t r♠ ♦♥② ♦r ♦♥ ♦ t s♣♥ ♣♦♣t♦♥s s s ♣rtr② tr ♦r ∆1 ♥ ∆2♦s ♥s r♦ss r♠ ①s② ♦r ♠♦rt② ♦r ♠♥♦rt② s♣♥ ♥♥rs♣t② ∆2′ ♥ ∆5 s②♠♠trs r♦ss t F ♦r ♦t s♣♥ ♣♦♣t♦♥s s♦t② ♦ ♥♦t rs t♦ s♣♥ ♣♦r③t♦♥ ♦ t rr♥t s t② ♣r♦ rr♥t ♦♥ ♥② rt ♦r♥tt♦♥ ♦ t rr♦♠♥ts

tr♦♥s t♥♥♥ r♦ss ♣rt② r②st♥ s②st♠ ♦♥sr ♦t tr s♣♥♥ s②♠♠tr② ♥ ♦ t P ♥ P ♦♥rt♦♥s t t♦t s②st♠ ♦♥t♥s t s♠ ♦ ♦♥t♥s rst♥ r♦♠ tr♦♥s t♥♥♥ ♦t ♠♦rt② ♥♠♥♦rt② ♥♥s r ♥ tr♥ t s♠s ♦ ♦♥t♥s ♦ s②♠♠trs ♥ ts ♥♥s s ♦♦♥ t t♦t ♦♥t♥ ♥ t Pstt s t s♠ ♦ ∆1 ∆2′ ♥ ∆5 ♥ t ♠♦rt② ♥♥ ♥ ∆2 ∆2′ ♥ ∆5 ♥t ♠♥♦rt② ♥♥ rs♣t② ♥ t P stt ♦r ♠♦rt② ♠♥♦rt②

Page 39: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❨❨

r ①♥ s♣t ♥ strtr ♥ ♦r ♦t ♠♦rt② ♥ ♠♥♦rt② s♣♥ Γ− s t Σ ♥ Λ ♥♦t ♥ ♣r♦♣t♦♥rt♦♥s ♥ t r s♣ rs♣t② ❬❪

tr♦♥s r♦♠ t ♥t♥ tr♦ t♥♥ ♥t♦ stts ♥ t ♠♥♦rt②♠♦rt② ♥♥ t♥ t ♦t♥ tr♦ t t♦t ♦♥t♥ s t s♠♦ ∆2′ ♥ ∆5 ♥ ♦t ♠♦rt②t♦♠♥♦rt② ♥ ♠♥♦rt②t♦♠♦rt② ♥♥s s♥ ♦ t t♥♥♥ ♦ ∆1 ♥ ∆2 s②♠♠tr② tr♦♥s ♥ t ♥t♣r s②s s♥♥t r♥ t♥ P ♥ P ♦♥rt♦♥s ♦ t s②st♠ st ♥ strtr ♦ t rr♦♠♥t tr♦s s ②t ♥♦tr ♣r♦♣rt② ♦ t♠♥t t♥♥ ♥t♦♥s tt s rs♣♦♥s ♦r t s②♠♠tr② tr♥

r♥s♣♦rt t♦♥s

tr t ♣r♦r♠ t♦♥s ♦r t s②st♠ ♥ sr t♥♥♥ ♦r ♦ t s♣rt ♦♥t♦♥ ♥♥s ② r ♣rs♥t ♥r ♥ ♥ s tt t ♠♦rt② ②♥ ∆5 s②♠♠tr② s ♣rs♥t ♥ t ss tts ♣ ♦ ♥t♥ t tr♦ ♦r ♦t♥ rt tr♦tr♦♥s t ∆5 s②♠♠tr② ①st t r♠ ♦r ♦t ♠♦rt② ♥ ♠♥♦rt②♣♦♣t♦♥s ♦ r♦♥ s♠ ♣♣s t♦ t ∆2′ ♥♥ ②t t♦ ts ②rt t s ♥♦t t♦ t② t♥♥ r♦ss t rrr

r r♥ s ♥ ♣rs♥ ♦r s♥ ♦ t ∆1 s②♠♠tr② ♥ t♦ ssr ①t♥t t ∆2 ∆1 s t s♦st ②♥ ♥♥ ♠♣sts rs♣♦♥st② ♦r ♠♦st ♦ t t♦t ♦♥t♥ ♦r ts s②♠♠tr② ♦s♥♦t stts t t r♠ ♠♦♥ t ♠♥♦rt② ♣♦♣t♦♥ s♦ t ♥♥♦t ♥t ♥t♦ t rrr r♦♠ t ♠♥♦rt② ♣♦♣t♦♥ ♦ t ♥t♦r ♥ t ♦tr♥ ♥ t ♥t♣r ♦♥rt♦♥ ∆1 s♣♥♣ tr♦♥s t♥♥ t♦rs ∆1 s♣♥♦♥ stts ♥ t ♦t♥ tr♦ ♥ tr r ♥♦ ∆1 s♣♥♦♥stts t② ♦♥t♥ t♦ t♥♥ ♥ s♥ ♦ s♣♥ ♦r s②♠♠tr②sttr♥ ♠r②

Page 40: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯

r ♥♥♥ ♦r s②st♠ t t rrr ♥ ♠♦♥♦②rs t t♦♣ t♦ r♣s s♦ t♥♥♥ ♥ t♣r stt t t ♦♥ ♦r ♠♦rt② ♥ t rt ♦♥ ♦r ♠♥♦rt② s♣♥ ♣♦♣t♦♥s ♦tt♦♠ r♣s ♣t t ♥t♣r ♦♥rt♦♥ ♦♥sst♥ ♦ t♥♥♥r♦♠ ♠♦rt② t♦ ♠♥♦rt② stts t ♣♥ ♥ r♦♠ ♠♥♦rt② t♦ ♠♦rt② sttsrt ♣♥ t♦♥ ♦tr ②rs r r♥ ♥ t ♥t♣r ♦♥rt♦♥t♦ s♦ ♦ ♥ s♥ ♦ s♣♥ ♥ s②♠♠tr② ♦r♥ t♥♥♥ ②♦♥ t rrr ♥ ♦r ♥ t ♦t♥ ♠t ②r s s②♠♠tr② s s♥t s ② t s②♠♠tr② ♦ t ♥♥t ♦ stt t t r♠ ♦ t ♥t♦r ♦t tt t ♥st② ♦ stts ss r ♦rt♠ ❬❪

♠♥♦rt② ∆2 stts ♥t ♥t♦ t rrr r ♣t t t ♦t♦r ♥ t P♦♥rt♦♥ t rt t② ♦♥t♥ t♦ ② ♥ t P stt

② s♠♣② s♠♠♥ ♣ t s②♠♠tr② ♥♥s ♠sr t t ♥ ♦ t♦t♦r ♦r ♦t ♣r ♥ ♥t♣r ♦♥rt♦♥s ♦♥ ♠② r② s tr♥ t♥ ♦♥t♥s ♥ ♦t P ♥ P ♦♥rt♦♥s s r♥♠♦st ♦t♥ s♦♥ s t r♥ ♥ rsst♥s s t ♥♥ ♥t♦r

Page 41: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❨❨

sst♥ ♥ sr t t ♦♦♥ ♦r♠

TMR =GP −GAP

GAP

=RAP −RP

RP

[%]

G ♥ R r t ♦♥t♥ ♥ rsst♥ ♦ t s②st♠ ♥ t ♣r P♥ ♥t♣r P ♦♥rt♦♥s rs♣t②

r ♥♥ ♠♥t♦rsst♥ rt♦ rss ♣♣ ♠♥t r♣♦rt♦♥ ① µm2 ♥t♦♥s t ♥♠ t rrr t r♦♦♠ t♠♣rtr rs ♥ ♠♣t② tr♥s ♦t♥ ② r❱♥♥t t ❬❪

s♦s t②♣ rsst♥ rss ♣♣ r ♠♥t s ♣♣ ♦♥ t s② ♠♥t③t♦♥ ①s ♦ t ②rs s♦ s t♦ P stt s② ①s s ♥ ♣♥ tr♦r t s ♣♣ ♥ ♣♥ s♣r♣♥r t♦ t rt♦♥ ♦ rr♥t ♦ ♥ ♠② s tt strt♥ t t ♥t t rt ♠♥t③t♦♥ ♦ t rr♦♠♥ts s ♣r ♦t♥ ♦♥ t ♥t ♥s ♥ t rsst♥ ♦ t s②st♠ s ♦ rt♦♥ ♦ t str♥t t♦ ♦s ♥♦t t t ♠♥t③t♦♥ ♦ t s②st♠♥t t rs ♣♦st ♥ ♦♥ ♦ t rr♦♠♥ts sts ts♠♥t③t♦♥ ♥ ♥s ♦♥ t ♣♦st rt ♦r♥tt♦♥ ♦ tr♦ ♠♥t③t♦♥ ♦♠s ♥t♣r ♥ t ♦r s②st♠ rsst♥ ♥rss ♠♥t③t♦♥ ♦ t s♦♥ tr♦ r♠♥s ♥♥ t ts ♣♦♥t t♦ts r ♦rt② ♥rs ♦ t ♠♥t str♥t t♦rs r ♣♦st s ss t ♠♥t③t♦♥ ♦ t s♦♥ tr♦ t♦ ♣ s ♥ t♦♥rt♦♥ ♦♠s ♣r ♥ ♦r ts t♠ ♥ ♦♥ t ♣♦st rt♦♥ rst♥ ♥ t ♥t ♦ rsst♥ ♥ ♠rr♦r ♦r♦rs ♦♥ t rtr♥ s♣ ♦ t r♦♠ ♣♦st t♦rs ♥t s

s t ∆1 s②♠♠tr② tr♦♥s r r② ② tt♥t t♥ t rrr t s♥ ♦ stts t ts s②♠♠tr② t♥ t ♠♥♦rt② s♣♥ ♥♥

Page 42: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯

rst② rs ts t♦t ♦♥t♥ ♥ ♥ ♣rs♥ ♦ t♦♥ str♦♥②tt♥t ∆2 s②♠♠tr② stts ♦s ♥♦t ♦♠♣♥st t ♦r♠r ♦ss s ♦♥ ♠②♦♥ r♦♠ t t r♥ t♥ ♠♦rt② ♥ ♠♥♦rt② ♥♥♦♥t♥s ♥ s♦ t rt♦ ♥rss t t rrr t♥ss s t∆2,2′ ♥ ∆5 s②♠♠trs ② ♠ str t♥ t ∆1 s♠♣ t♥ss♦r ♥♥♦t ♥rs ♥♠t② ♥ r♥ ♥♥♦♠trs t② r♦ss ②rs ♦♠s s♦ tt tr♥s♣♦rt ♠② r③ ♦♥② r♦ss tsts ♥ tr♥ strs ts ♦r♥② ♥♥ ♦ ts ts ♦♥ tr♥s♣♦rt r♦ss ♠♥t t♥♥ ♥t♦♥s sss ♥ t st♦♥ ♦r♥ ♣rt② r②st♥ s②st♠ ♦♥t♥ rt♥ ♥tr♥s trs ♥t②t ts s♣♥♣♦r③ t♥♥♥

♥tr♥s sss

❩r♦ s ♥♦♠②

r sst♥ ♣♥♥ ♦♥ ♣♣ s ♦ ♦23♦ ♠♥tt♥♥ ♥t♦♥ ♥ ♥ ♦r P t♦♣ ♥ P ♦tt♦♠ ♥♠♥tsst♥ r♦♣ ♦ ♠❱ s rrr t♦ t ③r♦ s ♥♦♠② ❬❪

❩♥ t ♦r t rst t♠ r♣♦rt ♥ ♥s② ♥♦♠♦s rs r♦ss 23s s t♥ s♠ s r♥ ♣ t♦ ♠❱ t s ♦sr ♦t t r♦♦♠ t♠♣rtr ♥ t t ♠ ♠♦r♣r♦♥♦♥ ♥ t ttr s s♣② ♥ t P ♦♥t♥ ♥♥ s t♥r② s ♦ ts ③r♦ s ♥♦♠② s ♦ t s♠ ♦rr s tt ♦ t ♠♥t①tt♦♥s t s ss♠ tt t tr♦♥s st ♦ t r♠ ♣r♦♦t ①tt♦♥s ♦ ♦ ♥tr s♣♥s rst ♥ ♥ t♦♥ t♦r ♥♦r♥ t s♥ t♥ ts s r♥ t rst t♦r ♥ t st♥rrrr t ♦r♥ ❬❪ t s ♦r t rst t♠ ♦sr ♥ sr♦r ♠♦r♣♦s rrrs t t s ♦♠♠♦♥② ♦sr ♥ r②st♥ s②st♠s s

Page 43: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❨❨

♥tr rs♦♥♥t stts

r ♦rt t♦♥ ♦ ♠♦rt② t ♥ ♠♥♦rt② rt ♦♥t♥ ♥♥s ♥ s②st♠ t ♠♦♥♦②rs t rrr r♣s t k‖ 6= 0 rst r♦♠ ♥tr rs♦♥♥t stts ❬❪

r ♠t sr ♥r② ♥s s♣rs♦♥ ♦r ♠♥♦rt② s♣♥ ♥♥ ♥ r② ③♦♥ ♣ts t ♥s rs t s ♥ s t s♣rs♦♥♦ sr stts ❲♥ t t♦ ♦r♣ t② ♦r♠ ♥tr rs♦♥♥t stts ♥ ♦♥trt t♦ t tr♥s♣♦rt t♦rs t ①♠♣ rs ❬❪

t♦♥s ♣r♦r♠ ② tr t ❬❪ s♦ tt ♥ t♦ ♠♥♦rt②♥♥ ♦♥t♥ r♦ss s s s ♠ ♦r t♥ t ♦♥ ♦ t♠♦rt② t s ♦♠♥t ② r ♣s ② r♦♠ t k ♥♦r♠ t♦ t rrr s trs r rt② rt t♦ t ♠♥♦rt② s♣♥ sr stts ss♠t sr stts r♦ss F t rt♥ k‖ ♦♥trt♦♥s r♦♠ts stt ♦♠ s♥♥t ♦♥ t ②r③s t ♥ s ts srstts ①st ♦♥ ♦t ss ♦ t rrr t② ♠② ♦♣ t♦ ♦tr rst♥ ♥

Page 44: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯

♥tr rs♦♥♥t stts tt r rs♣♦♥s ♦r r ♦♥t♥ ♣s ♥ t♠♥♦rt② ♦♥t♥ ♥♥ s ♥tr♥s trs ♦r t Gmaj/Gmin rt♦ s♥♥t② ts t t

♠♣t ♦ ♣♦♥♦♥s

♦ ♠♥t t♥♥ ♥t♦♥s s♦ rs ♦ t rt♦ t ♥rs♥t♠♣rtr ♣rt r♦♠ strtr ts sr ♥ ♣tr ts ss s♦t♥ ttrt t♦ tr♠② ♦r ♦t♥ ①tt♦♥s ♦ t rrr t♦♠s ♣♦♥♦♥s t♦ rt② ♦rs r♣♦rt tr rt ♠♣t ♦♥ t s♣♥♣♦r③ tr♥s♣♦rt rrr ♣♦♥♦♥s t ♥r② ♦ ♠❱ ♥ ♠❱ r r♣♦rt ♦♥ sr s②st♠s t ♦rrs♣♦♥♥ s ♥ t s♦♥ rt ♦rr♥t ♦t rtrsts d2I/dV 2(V ) s♦ ♥st tr♦♥t♥♥♥s♣tr♦s♦♣② ❬ ❪

tr rrr t②♣s

rrr s ♣rs♥t ♥ t ♦r♠r st♦♥s s ♥ s② ①♠♣ ♦ s♦stt s♣♥♣♦r③ t♥♥♥ ♥ t s②st♠ ♦r t♦ ♥trst♥ s②♠♠tr② tr♥ ts ♥ t♦ t rt sst② ♦ tr ♦♣t stss s ♦♥ r3 ♥ 2 ♥st♦rs r s♦ st r♥ ts tsss st♦♥ ♣rs♥ts ♣r♦♣rts ♦ ts ♠trs r♦♠ s♣♥tr♦♥ st♥♣♦♥tt♦ sr ♠♦r ♦♠♣① ♦♠♣♦♥s r ♣r♦♣♦s s rrrs ❬ ❪t② ②♦♥ t s♦♣ ♦ ts tss

tr♦♥t♠ tt♥t

r3 rt t♦ r②st③s ♥ ♥tr ♣r♦st 3

strtr s s♦♥ ♥ t ts tt ♦♥st♥t ♥ t s st♦ tr♥t♥ r ♥ 2 ♣♥s ❬❪

♦♠♣① ♥ strtr ♦r t ♣r♦st str♦♥t♠ tt♥t s ♣rs♥t ♦♥ ♦♠♣r t t rs♣t t♦♥ ♦r ♦♥ ♥ s② s tt t tr♦♥ tr♥s♣♦rt s ♥♦t ♦r♥ ② t s♠ tr♦♥ s②♠♠trs r3 rrr ①ts r② r♥t ♥ strtr ♣r♦r♦♠ tt ♦ s ts ♥ ♥ s ∆1 ♥ ∆5 s②♠♠trs rst♥ r♦♠♦①②♥ 2p ♦rts t ♦♥t♦♥ ♥ s ∆2′ ♥ ∆5 s②♠♠trs r♦♠ sts s t ♦♥sq♥ ♠♦r t♥ ♦♥ κ ♦♦♣ ①sts ♥ t ♣ ♥ t r♥trt② ♥ s t ♥trst♦♥ t♥ ts ♦♦♣s s ♦srt♦ t t ♦♥t♦♥ ♥ ♥ s♦ s t r♠ ♥ s ♦ ♦♥tt t ♠t s s s ♠♣r② t ♠ ♣♦t♥t ♦ s ♦♥ t♦ ♦st♦ t ♦♥t♦♥ ♥ ♠♥s tt F ♥ t st ♦r t♦ t ♥♦t ♦r ♦r tr♦♥ ♣r♦♣t♦♥ ♦♥ t rt♦♥ t tr♦♥ rrr

Page 45: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❨P

r Pr♦st 3 strtr ♥ s ♦ r3 A st②s ♦r r ♥ B♦r st rs♣t② ♦♠♠♦♥ ♦tr 6 r♣rs♥tt♦♥ t t B st♥ t ♥tr s s♦♥ ♥ t ♦tt♦♠t ❬❪

r ♦♠♣① ♥ strtrs ♦ r3 st②s ♦r t r ♥trt② ♠rs ♥♦t t ∆ tr♦♥ s②♠♠trs ❬❪

t ∆2′ ♥ ∆5 s t♥ ♦r t♥ tt ♦ t ♦s ∆1 ♥ ∆5 ❬❪ ♦r♦rt ①t♥s♦♥ ♦ t ∆5 s②♠♠tr② ♥ s t ♦♥ ①t♥♥ t st t♦rs κ s rst♥ ♥ t ♦♠♥♥t ♦♥tt② ♦ ts ♥♥ t♥ t rrrs ♥ ♦♥trr② t♦ t ♥ strtr ♣r♦ ♦r t r ♥trt② s ♥ t ♥tr ♦ t ♣ s ♦♥② ♦♥ ∆1 κ ♦♦♣ ♦♥♥ts ♦♥t♦♥ ♥♥ ♥s s②♠♠tr②

Page 46: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯

t♥♠ ♦①

tr♥t♥ ♦rr♥ ♦ r ♥ 2 ♣♥s t♥ t r3 r②st ♥ t♦ ♥ ♥rt♥ ♥tr tr♠♥t♦♥ ♥ t♦ 2 tr♠♥t♦♥ s♦sr t♦ ♠♦r ♥rt② ♦r t♥ r t ♥tr ♠①♥ ♠② r ♠♣t ♦♥ t t♥♥ ♠♥t♦rsst♥ rt♦ ♠♥s♥ ts ♦r♥ st♥ t s♥ ❬❪ ♥rt♥ ♥tr tr♠♥t♦♥ sr♥ ♣tr ♥ ♦rr t♦ ♦ t ss t t♦♥ 2 ②r ♠② ♣♦str♦♠ s♣rt ♣r tt♥♠ ♦① s♦r ♥tr ②r ♦ ♥sr t♥tr tr♠♥t♦♥ ♦ t rrr ♦r s♦♠ r♦♣s s♦ ♣rttt ♦② 2 rrrs ♦ ♦♦ ♥ts ♦r t s♣♥tr♦♥ ♣♣t♦♥s❬❪ tt♥♠ ♦① rrrs ♠t t♥ sr s ♥ tr♥t t♦ t str♦♥t♠tt♥t

r r②st♦r♣ tr ♠♥s♦♥ ♥ ♣♥r strtr ♦ ♥ts2 ❬❪

♥ts ♣s 2 s ♥ ♣ ♦ ❱ ❬❪ s t s♦ tt ♥♠♣t①② r♦♥ ②r s♦s ♦t rsstt② ♥ tr ♦♠♦♥t② t♥♦ ♦♥t ♦ts♣♦ts ❬❪ ts tt ♣r♠trs ♦r ♥ s♣② ♦r t rt♦♥ ♣r♦♠s s♠ tt ♠s♠t t ♣r♦st♠trs

t♥♥♥ ♦r ♦ t ♥ts 2 rrr s s♠r t♦ tt ♦ tr3 t♦ tr ♦rrs♣♦♥♥ ♥ strtrs s②♠♠trs ♦ t ♥ ♥r ♦ ∆1 ♥ ∆5 t②♣s t♦ ♣ ♦rts rs t ♦tt♦♠ ♦ t ♦♥t♦♥♥ ♦♥ssts ♦ s②♠♠trs rst♥ r♦♠ t♦♠s ∆2′ ♥ ∆5 ❬❪

s t t ♥ts ♣s ♦ 2r♦s ♣♦♥ ♦tr ♣r♦stss ♥ t♦♥ sst♦♥ tt t ♥ s s t ♦r tr♠♥t♦♥②r ♦ t r3 rrrs ♦r ♠② ♥ ♦♠ ts r♣♠♥t ♦r ts rs♦♥s♥ t♦ rt② sr ①♣r♠♥t rsts ♦♥ 2s strtrs trst② s s♦ ♣♣r♦ t♥ t t♠r♠ ♦ ts tss

Page 47: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

r♥t tr♦ ♠trs

r♦♥ s sr s t ♠♦ tr♦ ♠tr s ♦ ts ♥rst♦♦♥ strtr ♥ s②♠♠tr② tr♥ ♣r♦♣rts ♥ t s②st♠ ♦r tr r sr s♥ts ♦ t ♠♥t♦♥ s②st♠ t♦ ♣r♦♣rts ♦r♦♥ ts s② ♦①t♦♥ ♥ s♠t♥♦s ①st♥ ♦ rt♥ s②♠♠tr② ♥s♦r ♦t s♣♥ ♣♦♣t♦♥s s st♦♥ ♣rs♥ts ♣r♦♣rts ♦ r♥t ♠trstt ♠② s s rr♦♠♥t tr♦s ♥ ♠♥t t♥♥ ♥t♦♥s

♥tr♦t♦♥ ♦ ♦t

♥ ts sst♦♥ ♦tr♦♥ ♦②s ♥ ♣r ♦t tr♦s r ♣rs♥t s t②♣r♦ t♦ rt ♥ts ♦r ②♥ ♠♥t t♥♥ ♥t♦♥s t♦ tr ♦♦ s②♠♠tr② tr♥ ♣r♦♣rts ❬❪ ♥ ♦r ♥t♣② ♦ ♦①t♦♥ st

♦tr♦♥ ♦②s

r ♠t ♥ s♣rs♦♥ ♦ ♥ ♦ ♦♥ t ❬❪ Γ−rt♦♥ s♦ ♥ ♦tt ♥s r♣rs♥t ♠♦rt② ♥ ♠♥♦rt② s♣♥ s♥srs♣t② ♦tt♦♠ s ♦ t ♠♦rt② ∆1 s♥ r ♥ ♥ ♦rr t♦♦♠♣r t F ♣♦st♦♥ ♥ ♦t ♠trs ❬❪

s ♣rs♥t ♦r ♠♥t t♥♥ ♥t♦♥s ♦♠♣♦s ♦ r♦♥ tr♦s srr♦♠ t♥♥♥ rt♥ s②♠♠tr② ♥♥s ♥♠② ∆5 ♥ t♦ ssr ①t♥t t

Page 48: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯

r ♦t t♥♥♥ ♦r ♦♦ s②st♠ tt rrr ♥ ♠♦♥♦②rs t ♥ P t ♥ P rt rt ♦r♥tt♦♥ ♦ t tr♦s ❬❪

∆2′ tt r ♣rs♥t ♦t ♥ P ♥ P ♦♥rt♦♥s rsts ♥ ♦ ♦♥t♥ r♥ Pr♥ t ♣rs♥ts tt ② r♣♥ t ♦ tr♦s♦♥ ♠② ♥♥ t rt♦ s ♥ s② ①♣♥ ♦♥ ♦♠♣rs ♥s♣rs♦♥s ♦ ♥ ♦ ♦♥trr② t♦ t r♦♥ s ♦t ∆5 ♥∆2′ s♥s ♥ ♦t ② ♦ t r♠ ♥ t ♠♦rt②s♣♥ ♥ s♠♣s tt tr♦♥s ♦ ts s②♠♠trs ♥ ♦♥trt t♦ t t♦t ♦♥t♥♦♥② ♥ t ♣r ♦♥rt♦♥ rsts ♥ t r♣♦rt ♦♥ ♦s♥t♦♥s ♥ r t♥ ♦r tr r♦♥ ♦♥tr♣rts ❬❪ t♦♥s ♦ tt♥♥♥ ♣r♦r♠ ② ❩♥ t r s♦♥ ♦♥

s ♣r♦s② ♠♥t♦♥ r②st③s ♥ t strtr t tt ♦♥st♥t tt ♥ ♦r♠ r②st♥ ♥tr t ♦t ♦♥ ♦♥trr② ts t①♦♥♦s♣ ♣ ♦r♠ s♦♥ t ♦rrt tt ♠t♥ t t rrr ♦r t s ♥♦♥ tt t ♦ ♦♠♣♦♥ rt♥ t r♦♥ strtr ♣ t♦ ♦ rt♦ t ts tt ♦♥st♥t ♥ r② s♠r t♦tt ♦ r♦♥ ❬❪ ♥ t♦ ♥tr♠①♥ ♦ ♦ ♥ ♥ strtrs♥ ♦ s ♥t r♣♦rts s♦ tt t s t ♦ ♥tr tr♠♥t♦♥ tts ♥rt② ♠♦r ♦r rsts ♥ t sr ♠♦r ♦t ♥strtr t t ♥tr ❬❪ ♥ t ♦♥trr② r② r♥t rsts ② ♦♥ t s♦ tt ① t♥ t ♦x1−x♦r♠ ♠② s♦ t♦ ♥ ♥♥ rt♦ t♦ s♣ ♥ strtr ♠♦t♦♥ t ts rt♦ ❬❪

♥tr ♦t ②rs

s t s t ♦ ♥ strtr tt ♦rs ∆5 ♥ ∆2′ tr♦♥s r♦♠ t♥♥♥ ♥t P stt ♥ ♠♦r ♣r♦♥♦♥ ts r ①♣t ♦r t ♦ ♥tr

Page 49: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

r rt♦ ♦r ♦x1−x strtrs rt ♥rs♠ ♦♥t♦♥s ♥ ♠sr t r♦♦♠ t♠♣rtr s s t t ♠❱ s❬❪

r ♦t t♥♥♥ ♦r ♦♦ s②st♠ t t rrr ♥ ♠♦♥♦②rs t ♥ P t ♥ P rt rt ♦r♥tt♦♥♦ t tr♦s ❬❪

♣r♦♠ rst♥ r♦♠ t ♦r♠♥t♦♥ ♣ r②st♥ strtr ♦ ♦ts ♥♦t ♣rs♥t ♥ s ♦ ♣ t♦ ♠♦♥♦②rs t ♥♠ ♥tr ♦ ②rs ♦♦ t strtr ♦ t ♦r ♦ tr♦ t② r r♦♥ ♦♥t t tt ♦♥st♥t ♥ ❬❪ ❨s t ♦♠♣r t t♥♥ ♠♥t♦rsst♥ rt♦ ♦r sr strtrs rt t ♦♠♣r ♦♥t♦♥s ♦x1−x s②st♠s t t ① ♥ 1/2 ♦r r

Page 50: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯

sts r ♣rs♥t ♦♥ s ♦t♥ ♦r t ♣r ♦ ♦rtr♦ r r② ttr t♥ ♦r t ♦trs rt② ♦ ♦rt ♦s s②st♠ s ①♣♥ ② t ♥ ♦ t♦ ♣r♦r♠ tr♦ ♥♥♥t ♥ ♦rr t♦ ♦t♥ t tt ♣♥s t tr♥t♥ ♦ ♥ ♦♣t♦♥❬❪ t♦♥s ♣r♦r♠ ② ❩♥ t ♦♥ ②♣♦tt s②st♠s t ♦tr♦s s♦ s♠r rsts s ts ♣r♦r♠ ♦♥ t ♦s s②st♠

♦ s t①tr s②st♠s

s t s s②st♠s s♦ rs♦♥② s♥s t r♦♦♠ t♠♣rtrt② r ♣r♦♠s♥ ♥ts ♦r ♥tr♥ t ♥str st ♦r t ststrtr rqr ♦r ♣♦t♥t ♣♣t♦♥s rqrs ♦♥② ♦♥ ♦ t rr♦♠♥t②rs t♦ t♦ st t t ♠♥t ♣♣ t ♦tr s t♦r♠♥ ① s ♥♥♦t ♦♥ t trt♦♥ r♦♥ ♦r ♦ts s②st♠s sr ♣♦sst② t♦ ♣♥ ♦♥ ♦ t ②rs ♦r rsrrs t♦ ♦♦ ♦r ♥♦trs♦t♦♥s

r t strtr ♦ ♠♥t t♥♥ ♥t♦♥ rqr ② t ♥str② s②♥tt rr♠♥t ② ts s ♣♥♥ ②r ♦ t strtr ♥srs str♦♥ ①♥s ♥ s♠ str② ♠♥t s t♥ ♦♥ t t♦♣ ②r♥② t t♦♣ r ②r ♥ st ts ♠♥t③t♦♥ t s ♣♣ ❬❪

♣♥♥ ♦r tr♦ ♥ rt s s②♥tt rr♠♥t ② ♦♠♣♦s ♦ ♥trr♦♠♥t② ♦♣ rr♦♠♥t♦♥rr♦♠♥trr♦♠♥t strtr ①♥s ② t ♥trr♦♠♥t ②r ♥ ①♠♣♦ s strtr s s♦♥ ♦♥

♦r ♠♦r t♥ ②rs ♠tr ♥♥rs r ♦♦♥ ♦r ♥ ② strtr t str♦♥ ①♥s ♥ ♠♥♠♠ str② ♠♥t s t♥ ♦♥ tr ②r ♦ r t ♠♦st ♣r♦♠s♥ ♥ts r r♥ ♦r Pt♥ s t ♥trr♦♠♥ts ♥ ♦♦ s t s②♥tt rr♠♥t ❬❪ ♦r t

Page 51: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♠♥ ♦st ♥ ♣♣t♦♥ ♦ ts ♠trs ♥t♦ t ♠♥t t♥♥ ♥t♦♥ss tt tr r②st♥ ♦r♥tt♦♥ ♦s ♥♦t ♦♦ t strtr ♦ t rrr ♥st t s ♦r♠ ②♥ r tt ♠s♠t tt♦s ♥♦t ♦ t rrr t♦ r♦ t♦♣ ts ② ♠t②r s t sr♠♦♥♦r②st s♦t♦♥ t♦ ts ♣r♦♠ s ♦♥ ♥ ♦r♠ ♦ t ♦ tr♦s

r ♠t ♣tr ♦ t ♦♦ strtr rr②st③t♦♥ r♥ t ♥♥♥ ❬❪

♦ s ♥ ♠♦r♣♦s ♠tr s♦ t rst ♠♦♥♦②rs ♦ r♦ ♠♦r♣♦s② ♦♥ t♦♣ ♦ t ♦r ♦♥ rt♥ ♥♠r ♦ ②rs s r♦♥ ♠♦r♣♦s② t r②st♥ strtr strts t♦ ♣♣r ❬❪ s s ♥♦t ♣t①t rtr t①tr r②st ♦♠♣♦s ♦ r②st♥ ♦♠♥s s♣rt ②r♥ ♦♥rs ♥ ♠♦r♣♦s r♦♥s ♣♣r ♦ tr♦ ♥ r♦s♦♥ s t①tr ♠♦r♣♦s② s ♣rs♥t ♦r t r②st♥t② ♦ t♠♥t t♥♥ ♥t♦♥ s ss♥t ♦r rs♦♥ rt♦ r②st③t♦♥ s tr♦r ② ♥♥♥ t ♥tr st t t♠♣rtr ♥♦t ♦rt♥ rsts ♥ s♣r ♦ t r②st♥ strtr ♦r♥t♥ r♦♠t t①tr rs ♦ t rrr ❬ ❪ ♥ t r②st③t♦♥ rs t♥st♦rrr♦♠♥t ♥tr t ttr strts t♦ ♦r♠ t strtr s ♣t♥ t♦ t strtr ♥st ♦ ♦r♠♥ ts st ♣s ③ t s♦ tt s♣t t ♣♦②r②st♥ ♥tr♦ t rrr tr s r② tt ♦r ♥♦ ♥♥ ♦♥ t tr♦♥ tr♥s♣♦rt ② tr♥ ♦♥rs ❬❪ s ♦ ①♣t t t♥♥ ♠♥t♦rsst♥ sr② s♠ ♦♥ t ♥♦♥♥♥ ♠♦r♣♦s s②st♠s s ♦♠♣r t♦ t ♥♥♦♥s s ♦ t s②♠♠tr② ♠①♥ rst♥ r♦♠ t ♥♦r♥t tr♥s♣♦rt tts t②♣ ♦r ♠♦r♣♦s rrrs ❬❪

♦s ♠♥t t♥♥ ♥t♦♥s ♣r♦ t♦ ♥♦t ♦♥② ♣r♦♠s♥ ♥ts ♦r ♥str ♣♣t♦♥s t t t♥♥ ♠♥t♦rsst♥ ♦sr ♥ts strtrs s ♠ r t♥ tt ♥ st♥r ♥ ♦s s②st♠s❬❪ s s t♦ t♦ t ♠♣t ♦ t t①tr③t♦♥ ♣r♦ss ♦♥ qt②♦ t ♥trs sss ♥ st♦♥ ♥ t ♦tr ♥ r② r♥t ♦r ②

Page 52: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯

r t sr♣rs♥② s♦s tt ♣ t♦ rt♦ ♠② s♦ r♦♠ t t①tr s②st♠ ❬❪ ♦r♦r rr t r♣♦rttt r♣♥ t ♦r ♦ tr♦ t t ♦♦ ②r ♠♣r♦s♦t r②st③t♦♥ ♥ ♥ tr♠ stt② ♦ t ♥t♦♥ ♦♥sq♥t②s t♦ ts ttr ♣r♦r♠♥ ♥ ♦♠♣rs♦♥ t♦ t st♥r ♦s s②st♠❬❪

0.7r0.3♥3 ♠t tr♦s

♥ tr ♥t ♥♥ ♥t♦♥s r② ♦♥ tr t♦rs s♣♥♣♦r③t♦♥ ♥ t ♥t♦r ♣♦ss② ♦r s♣ tr♦♥ s②♠♠tr② r♥ ♥s②♠♠tr②♣♥♥t ② rts t♥ t rrr ♥ ♣t♥ ♦r rt♦♥♦ s②♠♠tr②♣♥♥t stts ♥s t ♦t♦r ♥♦② t♦ t ♣♦♥t ♥ st s②st♠ ♠♦t♦♥ ♥ t♦ rr s♣♥ ♣♦r③t♦♥ ♠②♥♥ t t♥♥ ♠♥t♦rsst♥ ❯♥♦rt♥t② t s♣♥ ♣♦r③t♦♥t♥ t rr♦♠♥ts s rt♥ ♥t ♦s ♥♦t ♦ t♦ ♥♥t rt♦ rtr

♥ r♦♦t t ♥tr♦ ♠trs t ♥ strtr ①♥ s♣tt ② tt ♦♥ ♦ tr s♣♥ ♣♦♣t♦♥s ♦ ♦♥t♥ rs t ♦tr♦♥ ♦ s♠♦♥t♥ ♦r ♥st♥ ❬❪ ② r ssq♥t② ♥♠♠ts

❲t♥ t t♠r♠ ♦ ts tss ♣r♦ss ♦ ♦t♥♥ ♥t♦♥s t ♠t ♥t♥♠ str♦♥t♠ ♠♥♥t 0.7r0.3♥3 tr♦s rt s ♣♣r♦ s st♦♥s srs ♥♠♥t ♣r♦♣rts ♦ tsstrtr

r②st s♣tt♥

♥ ♦rr t♦ ♥rst♥ t ♠t ♦r ♦ rt♥ ♠trs tr ♣②s ♣r♦♣rts ♥ t♦ sr 0.7r0.3♥3 ♦♠♣♦♥ s ss♥t②t r♦♣ ♥t♥♠ ♠♥♥t ♥3 ♦r r②st③s ♥ t♣r♦st 3 strtr r② ♣rs♥t ♦r t r3 rrrs ♦♥ ♥ t s t A ♥ B s♣rs ♦rrs♣♦♥ t♦ ♥t♥♠ ♥ ♠♥♥srs♣t② ❯♣♦♥ ♦♣♥ t t str♦♥t♠ s♣ ♣r♦♣♦rt♦♥ ♦ t sts s r♣ ② r

♥♥s ♥ tr♥st♦♥ ♠t s ts ♠♦ ♥ ♣r♦strtr ♥ s ♦ t ♦tr 3 s②♠♠tr② ♦ ♠♥♥ts t♦ ♦ ts♦ ♥rt s ♥♠ g r rt t♦rs t ♥t② r♦①②♥ sts tr ♦ t♠ t2g r ♥ ♦♥s t♥ t♦s sts

t♦ t ♦♦♠ r♣s♦♥ t♥ t ♥ ♦rts ♥ ♥t② r♥s sts t ♥r② ♦ t g ♦rts rt t♦rs t sts rss s

Page 53: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

r s♣ ♦ t ♥ st ♥t♦♥s r♦♠ t t♦ rt ♦♣ g ♦rts dx2−y2 dz2 ♦tt♦♠ t2g ♦rts dxy dxz dyz ①tr♥ rs♣t ♦①②♥ sts ❬❪

r ♥r② s♣tt♥ ♦ ♦ ♥rt ♥ ♦tr r②st❬❪

♦♠♣r t♦ t ♥r② ♦ t t2g s s ∆CF ♥ s♣tt♥ ♦♥r② s t♦ t r②st

♦r♥ t♦ ♥s r tr♦♥s ♦rts s♦ s t♦ ♠♥♠③ t ♦r♥r② ♦ t s②st♠ ♦r ♥ ♦♥ t ♦r tr♦♥s s t s ♦r t♥3+ ts ♥ ♦♥ t♦② rst tr tr♦♥s ②s ♦♣② t ♦st♥rt t2g s t ♦ tr s♣♥s rt ♦♥ ② t t ♦r ♦t ♦rt tr♦♥ s r♥ ② t rt♦ t♥ t ∆CF ♥ t ♥s rst③t♦♥ ♥r② H ∆CF > H t s ♠♦r ♦r ♦r t tr♦♥ t♦

Page 54: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯

r P♦ss ♦s♣♥ ♥ s♣♥ stts ♦ ♥3+ ♥ ♦trr②st t ttr ♥ ♦r ♥ tr♥st♦♥♠t ♦①s ❬❪

st ts s♣♥ ♥ ♦♣② t ♦st t2g ♦r ♥ t ♦♣♣♦st H > ∆CF

stt♦♥ t tr♦♥ ♦♦ss t g s t♦ stt♦♥s r rs♣t② ♦s♣♥ ♥ s♣♥ stts ♥ s ♦ ♠♦st ♦ tr♥st♦♥♠t♦①s ♥3+ ♥ ♥♦ ①♣t♦♥ t s♣♥ stt ♦♥rt♦♥ s ♥rt②♠♦r ♦r t2g tr♦♥s ♦r♠ t tr② ♥rt ♦r s♣♥ t gtr♦♥ s ♦♣ t♦ t ② ♥s r ♦♣♥

♦ ①♥ ♠♥s♠

♥ ♦rr t♦ ①♣♥ t ♠t ♥tr ♦ t t s ♠♣♦rt♥t t♦ ♥rst♥ t ♠♣t ♦ t ♦♣♥ t r t♦♠s s ♥ ♥trr♦♠♥t♠tr ♥ ts ♥ ♦♥ stt s s s♦♥ ♦♥ ❲t♦t ♦♣♥ts t x ♥t 1−xrx♥3 ♦r♠ s ③r♦ ♥ ts ♦♥ ♦♠♣♦st♦♥ s 3+♥3+2−

3 ♦r r♣♥ ♦♥ tr♥t t♦♥ ♦ ♥t♥♠ t ♥t str♦♥t♠ r♠♦s♦♥ tr♦♥ r♦♠ t s②st♠ s rst t ♥3+ ♦♥ ♦♠s qr♣② r♥4+ ♥ ♦ ♥ t g s♥ s ♦ t r②st♥ s②♠♠tr② ♦t s②st♠ t ♥ ♦♥s r t♦♦ r ♣rt t♦ ♦r♣ ♥ ♥ tr♦♥ ♥♥♦t tr♥srr rt② t♥ t♦ r♥t② ♦♥③ ♥ sts ♥ 2− st s t♦ ♣② r♦ ❩♥r s♦ tt t tr♦♥ tr♥sr t♥ t♦ ♥ sts s r③ ②♦♣♣♥ ♦ ♦♥ tr♦♥ r♦♠ t ♥ st t♦ t 2− st ♥ t s♠t♥♦s ♠♣♦ ♥♦tr tr♦♥ r♦♠ ts 2− st t♦ t ♦tr ♥ st ❬❪ s ♣♥♦♠♥♦♥s ♦ ①♥ ♦r♦r ♦♥ tt t s♣♥ ♦ t tr♥srrtr♦♥ ♦ ♦♣ t ♦t ♥♥s ♦♥ ♦rs ♦♣♣♥ ♠♣t tsstr♦♥② ♣♥s ♦♥ t rt s♣♥ ♦r♥tt♦♥ ♥ ③r♦ ♦r t ♥t♣rs ❬❪ s ♥ ♥ t ♣r ♥♠♥t ♦ s♣♥s tr s ♦♥② ♦♥ s♣♥t②♣ ♦tr♦♥s ♠♦♥ t t g s ts rsts ♥ t ♠tr ♥ ♦♥t ♦rt ♠♦rt② s♣♥ ♣♦♣t♦♥ ♦♥② ♥ rs t♦ t ♠t ♦r ❩♥r ♠♦ s rtr ①t♥ ② ♥rs♦♥ ♥ s ❬❪

Page 55: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

s t ♣♦♥ts ♦t tt t ♦ ①♥ ♠♥s♠ s ♥♦t t ♦♥②rs♦♥ ♦r t rrr ♦♣♣♥ ❬❪ ② ♦♥ s♦t♦♥ t♦ t sr♣♥② t♥rt♥ s♣ts ♦ t t ② ♣r♦♣♦s♥ str♦♥ tr♦♥♣♦♥♦♥ ♥trt♦♥ rs♥r♦♠ t ♥r ♥r② t♥ ♦ t ♦tr ♥ s ❬❪ ss♥t②s♣♥ t ♥r s♣tt♥ rss r♦♠ t ♦♠tr st♦rt♦♥ tt r②st♥ s②st♠ ♥r♦s ♥ ♦rr t♦ ♦r ts ♦r ♥r② t s ts st♦rt♦♥tt ts t ♥r②

r t ♠t ♣tr ♦ t ♦ ①♥ ♠♥s♠ ♥0.7r0.3♥3 t♥ ♥3+ ♥ ♥4+ sts ssst ② ♦①②♥ ♣ ♦rts gs s♣t ♥ ♥3+ s s ② t ♥r r②st♥ tt st♦rt♦♥ t ♣♥rs♦ ♥ strtr ♦ t 0.7r0.3♥3 ❬❪

s♠t ♣tr ♦ ♦ ①♥ t♥ ♥3+ ♥ ♥4+ sts t①②♥ ♣ ♦rts ♣t♥ t ♥r ♥r② st♦rt♦♥ ♦ ♦t g ♥t2g s ♦ ♥3+ s s♦♥ ♦♥ ♦♥ t t rst♥ ♠t ♥strtr ♦ t ♠tr

s ♥3 s ♥ ♥trr♦♠♥t ♠tr t t ♥rst ♥♦rs ♥♦♣♣♦st s♣♥s ♥ tr♦♥ ♥♥♦t s♠♣② ♦♣ t♦ t ♦tr st s t str♦♥♥ r ♦♣♥ ♦rs t t♦ ♣ ts s♣♥ ♣r t♦ t ♦♥ ♦ t st t ♦♣♣♥ ♦ t tr♦♥ s t♥ rst② r ♦r t sts t t s♣♥s♥t♣r rt② t♦ tt ♦ t tr♦♥ s s♦♥ ② ♥♥s ♥rs♥t ♠♦♥t ♦ r rrrs t♥ t ♠tr ss t ♦r♥ ♥trr♦♠♥t strtr t♦ ♦♠ ♥t ♥ rr♦♠♥t② ♦rr ♦♠♣♦♥♥ts strtt♦ ♣♣r ❬❪ t rt♥ ♦♥♥trt♦♥ ♦ ♦♣♥ts t strtr ♦♠s ②rr♦♠♥t s x ♦♣♥ rt♦ s ♦♥ t♦ t♥ ♥ s♦ t s tsrt♦ rt♦ tt s ♦♠♠♦♥② s ♥ ♦♠♣♦♥s rt♦♥ s s② s t♦ sr s r ♦♣♥ ♦ t strtr ♥ s ♥♦tt♦♥

Page 56: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯

s t♥ ts ♠♥sr♣t t ♠② ♥trst♥ t♦ ♥♦t tt ♦r♦♣♥t ♥3 s②st♠ t str♦♥t♠ ②s ♥st♥ stt s ♥♥t ♦rt ①♣r♠♥t ❬❪

♠♣rtr ♣♥♥

♠♥ ♦st ♥ ♠♣♠♥tt♦♥ ♦ ♠t ♠trs t♥ ♦♠♠r♠♥t ♥t♦♥s s t t♠♣rtr ♣♥♥ ♦ tr ♣r♦♣rts ♦ ♠♥♥ts ♥t♦♥s rss r♣② t t♠♣rtr ♥s♣♣rs ♦ t r♦♦♠ t♠♣rtr ② ♦ r t♠♣rtr ♦ t s ❬❪ t s ①♣♥ ♥ ♦r♠ ♦ ♣r♠tr ♦ss♦ ♣♦r③t♦♥ t ♥trs s t s t ♥tr s♣♥ ♣♦r③t♦♥ tttr♠♥s t t♥♥♥ ♣r♦♣rts Pr t s♦ ❬❪ tt t s♣♥ ♣♦r③t♦♥♦ r sr rss ♠ str t ♥rs♥ t♠♣rtr t♥t ♠♥t③t♦♥ ♦ t ♠tr r t♠♣rtr ♦r♥ s♠r♠♥t③t♦♥ ♥ rt♦♥ ♦ t ♠t rtr ♥ ♥♠ t ♠♥♥t②rs r r♣♦rt t♦ rst ♥ tr ♥ rr♦♠♥t ♣r♦♣rts ❬ ❪

r ♠♣rtr ♣♥♥ ♦ t ♥tr s♣♥ ♣♦r③t♦♥ ♦r r♥trrrs ♦♠♥ t ♦♠♣r t♦ tt ♦ t r sr ♥ t♦ ts ♠♥t③t♦♥ ♦t♥ ② Pr t ❬❪

r t ♣r♦r♠ ♠sr♠♥ts ♦♥ t t♠♣rtr ♣♥♥ ♦ ♣♦r③t♦♥ ♦r r♥t ♥st♦r ♥trs ❬❪ ♥ ♦♠♣r t♠ t ts♦t♥ ② Pr ♦r t ♥ r sr ♦ t rsts♦s tt t ♥tr ♣♦r③t♦♥ rs rs♠ t ♦♥ ♦ t ♠♥

Page 57: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

t③t♦♥ rtr t♥ sr ♣♦r③t♦♥ ♥t♥ tt t ♠♥ts♠ s♣rsr ♥♦t st t t sr t ♥ t ♥t② ♦ t ♥tr t♦ trt t♠♣rtr s r♦♥ ♦r

r♥ ♥ t s♣♥ ♣♦r③t♦♥ ② t♥ t sr ♥ t ♥tr s ♥ t ♣rsrt♦♥ ♦ t 6 ♦tr t t sr B sts ♥♠♥♥s s r t ♦tr♠♦st ②rs ♠② ♦①②♥ ♥t rsts ♥ r s♣tt♥ ♦ t g s s rst t ♦ ①♥ ♠♥s♠ s ♥ ♥ t ♠♥t♦♥ t♠♣rtr ♣♥♥ s♦s r② r♥trtr r♦♠ tt ♦ t ♥tr ❬❪ ♥ t ♦tr ♥ t ♦♥t♥t② ♦ ts♦tr s ♣rsr t t ♥trs t t ♠♥t♦♥ ♦r 2 ♥♥ ♥ t ♣rs♥ ♦ st♦rt♦♥s ts ♠♣t ♦♥ t tr♦♥ strtr s ♦rt♥ ♥ t s ♦ t r sr rsts ♥ ♠♦r rtr t t t s t rs ♦ t r rrr ♥st② ♥ t trt♦♥ ♦ t6 strtr ♦♠tr② t t ♥trs tt r rs♣♦♥s ♦r t C rt♦♥❬❪

s②st♠

r ♥st② ♦ stts ♦ t s②st♠ t qr♠ Φe

♥ Φh ♥♦t tr♦♥ ♥ ♦ rrr ts rs♣t② t2g ♦rrs♣♦♥s t♦ t∆2′ ♥ ∆5 s②♠♠trs t g r♣rs♥ts ∆1 ♥ ∆2 s ♣r♦s② s♦♥ ♦♥t ❬❪

s♠t qr♠ ♥♠♥t ♦ t ♦r♠♥t♦♥ ♥s ♦r t ♦♠♣t ♦r♥t s②st♠ s s♦♥ ♦♥ s ①♣♥

Page 58: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯

r rsst♥ ♣♥♥ ♦♥ ♠♥t ♣♣ ♦r µm2 t ❬❪

♥ st♦♥ t s♥t② ♦ t♠♣rtr tr r ♦♥② ♠♦rt② s♣♥ stts t t r♠ ♦ tr♦s rs t ♠tr s ♥st♥ ♦r t ♠♥♦rt② s♣♥ s♣♥ ♣♦r③t♦♥ ♦ t tr♦♥s t♥♥♥ tr♦t strtr s tr♠♥ t♦ t ♥ ♥ r ❬❪ rst♥ ♥r② t♦t s♣♥ ♣♦r③t♦♥ t ♦ t♠♣rtrs s rs t♦ r s ♦♦ss t♥♥ ♠♥t♦rsst♥ ♦r s♦rt② ♦♦ss ♠♥t♦rsst♥ ♠sr♠♥t ②♥ s s♦♥ ♦♥ ②s r♣② t t t♠♣rtr ♥ t s♣♣rs t t♦ t ♦ss ♦ t s♣♥♣♦r③t♦♥ t t ♥trs ❬❪

Page 59: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♣tr

♦ ♦ ts

r②st♥ s②st♠s ♣rs♥t ♥ t ♣r♦s ♣tr ♠② sr r♦♠ ♠♣rt♦♥s rst♥ r♦♠ t r♦t ♦ s♥ ②rs ♦♥ t♦♣ ♦♥ ♥♦tr s♠♣s tt t ♥② ♦ t s♣♥tr♦♥ rs♣♦♥s ♣rt t♦rt② s ♦t♥s♣♣rss ② t♦♥ ts rs♥ r♦♠ t ♣rs♥ ♦ ts s t t♦♥tr♦ ♥ rtr③t♦♥ r r t♦ ♦t♥ s s♦♥ sr ♦r t s tr♦r ss♥t t♦ ♥rst♥ tr ♦r♥ ♥ ♣r♦♣rts s ♣tr♦ss ♦♥ sr t②♣s ♦ t♥ stt♦♥s tt t♦ t ♣rss ♠♥t♦rsst rs♣♦♥s rst st♦♥ ♥♦♠♣sss t ♦ t st② t♥r②st♥ trs tt s s t♥♥ rrrs ♥ t ♥♥ ♦ ts ts ♦♥ t s♣♥♣♦r③ tr♥s♣♦rt t ♥ ♠♣ss ♦♥ ♦♣t ♠♥s t♦ ♥t②ts ts s♦♥ st♦♥ ♦♥♥trts ♦♥ t♦♥s r♦♠ ♥♦♠♥ r②ststrtr t ♥trs t s♦ srs sts ♠t♦s ♦ s♣♣rss♥ ♦r♠♥s♥ t r♦ ♦ ts strtr ♠♣rt♦♥s tr st♦♥ srs♣♥♦♠♥ ♦ tr♦♠rt♦♥ ♥ ♦ ♦♥ ♥ s t s t♦♦ t♦ ♥♥ ts♣♥tr♦♥ ♣r♦♣rts ♦ tr ♥t♦♥s st st♦♥ ♥tr♦s rs ♦rsr ♦♥ ♠♥ts♠ t♥ r②st♥ trs t♦ ♣rs♥ ♦ ts ♥♥♦♣ ♥st♦rs

♠♣rt♦♥s

s st♦♥ srs ♣r♦♣rts ♦ strtr ts ts rst sst♦♥♦♥♥trts ♦♥ tr ♠♣t ♦♥ s♣♥♣♦r③ tr♥s♣♦rt ♥ rst♥ sr♣♥st♥ t♦rt ♣rt♦♥s ♥ ①♣r♠♥t ♦srt♦♥ rs t s♦♥♦♥ ♣rs♥ts ♦♣t ♣r♦♣rts ♦ t t sts

♠♣t ♦♥ s♣♥♣♦r③ tr♥s♣♦rt

rs♦♥ ♦r ①♣r♠♥t rsts ♦♥ ♠♥t t♥♥ ♥t♦♥s rr② ♠tt t♦rt ①♣tt♦♥s s ♣rt② ♥ ♣rs♥ ♦ ts t♥ tr r②s

Page 60: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P

r ♠t ♣tr ♦ ♦ ♦r♥ ♦ t t rrr t t♦♣rs♥ ♦ t stt

t♥ ♥t♦rs ♥ t ♣rs♥t t♥ rrr rts ♥ t♦♥ ♥r② ♥ t ♥ ♣ ♦② r♥ t t rrr t ♦ t ♠tr tr♦♥s r♦ss♥ t rrr ♦ t♥♥ ts stts ♦ ♦r ♥r②t r sttr♥ ts ♠♥s♥ t ♦r ♥t♦♥ rsst♥ ❨t ♣rtr♦♠ t r s②st♠ ♦♥t♥ ts t ②t ♥♦tr ♠♣♦rt♥t ♣r♦♣rt②♦ ♠♥t t♥♥ ♥t♦♥s s♣♥ ♣♦r③t♦♥ ♥ s②♠♠tr② tr♥ ❬❪

rs ♥ ♣rs♥t ♥ t rst ♣tr ♦ ts ♠♥sr♣t s♦ ♦♠♣① ♥ strtrs ♦ r②st♥ ♥st♦rs r ♦ t ♥trst ♦ ts tsst s ♣rs♥t ♦r♥ ♦ t s②♠♠tr② ♦ ♥s tr♠♥s t s②♠♠tr②♦♥sr♥ ♦r♥t tr♦♥ tr♥s♣♦rt r♦ss t rrr ♥ ♥r stt ②♥♥ t ♥ ♦r ♦♥t♦♥ ♥ ♦ t ♥st♦r s ♦♣t t s②♠♠tr② ♦ tt♥ s ♦♥ ♥rt② trrss t ♥ ♣ ♥ t s ♦ t sttt s②♠♠tr② rtr ♦ tt t stt s ♦ r♦♠ tt ♦ t ♥t♦ tt ♦ t ♦♥t♦♥ ♥ ♠ s ♦ ♠t♥ ♣ stt rs♥r♦♠ r tr♥sr t ♠ttr ♥tr ❬❪ s t ♥ ♥r② t stt ♦♣t t rtr ♦ t ♥ ♥ ♦♥t♦♥ ♥stts ♣r♦♣♦rt♦♥ ♦ ♦ ts rtrs s ♥ tr♥ ♥rs② rt t♦t κ ♦ t ♦♠♣① ♥ ♦♦♣ ♦ t rtr ♦♥sr ♥ t ts t st ♣rt② ♦ t ♥♦♠♥ tr♦♥ s②♠♠tr② t ♠② ♣t ts tr♦♥♥ t t stt s ♦♣ t t♠ ♦t♦♥ ♦ t t stt s ♣r♦ s ♥r ♦♠♥t♦♥ ♦ t t♦ ♥ ♥ ♦♥t♦♥ ♥ s②♠♠trsr♥s♣♦rt ② r♦♠ t t stt s t♥ ♣r♦ s ♥r ♦♠♥t♦♥ ♦t t♦ s②♠♠trs tt sr t t stt ts t② ♥ t♦ ♠①♥ t♥ s②♠♠tr②♣♦r③ ♦♥t♦♥ ♥♥s ♣♥♥ ♦♥ t ♥st②

Page 61: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❯ P

♦ t t stts t♥ t rrr s ♣r♦sss ♠② ♣♣♥ ♠t♣ t♠srst♥ ♥ s♥♥t rt♦♥ ♦ t s♣♥♣♦r③ tr♥s♣♦rt ♦r♥② ♥ ♦♥sq♥t② ♦ t s♥ ♦ t s②st♠ ♦r♦r ♥ ♦rr t♦ ♦r♦♠ t♥r② r♥ s ♦♣♣♥ t stts ♠② ♦♠♣♥ ② ♣♦♥♦♥♠ss♦♥ ♦r s♦r♣t♦♥ r♥ t tr♥st♦♥ ❬❪ s ♥tr♦s ♥ t♦♥♥st t♠♣rtr♣♥♥t ♦♥t♥ ♥♥ ♠② rs♣♦♥s ♦rs♣♥♣♣♥ ♥ts ❬ ❪

r t♦♣ ♥ rsst♥ ♦tt♦♠ s t ♥t♦♥ ♦ t rrrt♥ss ♦r ♦t♦ s r♦♥ ♦♥ r♥t r ②rs❬❪

♥ t♦ t t♦rt t♦♥s ♣rt tt tr s ♥♦ ♠t ♦ rt♦ ♥ ♣rt② ♣t① ♥t♦♥ t r② t rrr ❬❪ ♥ ♥♦r ♥♠ t rrrs t t♦r② ♣rts r② s♥s ♦r r♦s s②st♠s♣r♦♣rts ♦ tr r ♦♥tr♣rts r s♥♥t② ss stst♦r② r s♦s tt ♥ t♦ rsst♥ ♦ t ♥t♦♥ ♠♦st ♥r② ♥rss t tst♥ss t rt♦ ♦sr rs rt♥ ♠①♠♠ tr t strts t♦rs ♥ ♥t② rs ③r♦ t s ♥t ts ♠①♠♠ tt t ♦r♥t t♥♥♥ sr ♥ st♦♥ ♦♠♥ts t ♦♥t♥ trrs r♠♥♥

Page 62: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P

tr♦♥s t♥♥ ♦♠♥♥t② t sts r② ♠①s tr s②♠♠trs♥ ♥t② rsts ♥ t s♣♣r♥ ♦ t s♥

r♦♣ ♣r♦t rrr t tMgO anneal r❬❪ ❬Ωµm2❪ ❬❱❪ ❬♥♠❪ ❬❪

♦② ❬❪♥② ❬❪rts 20K 20K F+∗ ❬❪♦♦r ❬❪♦♥t♥ ❬❪Ptr♦ 3K ❬❪Ptr♦ 3K ❬❪ 5K 5K ❬❪ 5K ❬❪ 5K 5K) ❬❪❨s 20K 20K) ❬❪ ❬❪ ❬❪❳♦ ❬❪

♦♠s 13K ❬❪

♦♠♣rs♦♥ ♦ r♥t st rt♦s r♣♦rt ② sr r♦♣s ♦♥♦s s②st♠s ♦♥ t tr rs♣t ♥♥♥ t♠♣rtrs

r♦♣ ♣r♦t tMgO rrr t r❬❪ ❬Ωµm2❪ ❬♥♠❪ ❬❱❪

♥ ❬❪s♥ ❬❪❨s 20K ❬❪

♦♦r 1K def bar MF ❬❪♦♥t♥ ❬❪❨s 20K 20K RT M ❬❪s♥ ❬❪❲♥ ❬❪

sts ♦r s②st♠s s t♦rt ♣rt♦♥s ② ❲♥ t

♥② r♦♣s t ♦tst♥♥ ①♣r♥ ♥ t♥ ♠s r♦t ♥ rt♦♥♦ t ♠♥t t♥♥ ♥t♦♥s r♣♦rt s ♥t② ♦r t♥ ts♣rt ② t t♦r② s s♠♠r③ r♥t r♣♦rts ♦♥ sr t②♣s♦ s ♠♥t t♥♥ ♥t♦♥s r♦♠ r♥t r♦♣s

♥ t s ♦ ♥♦♥♦s s ♦r t♦rt t♦♥s r♣r♦r♠ ♦♥ ♠② s r sr♣♥② t♥ t ①♣r♠♥t ♥ t t♦r②

Page 63: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❯ P

r♦♣ ♣r♦t tMgO rrr t r❬❪ ❬Ωµm2❪ ❬❱❪ ❬♥♠❪

Pr♥ 5K F F ∗ ❬❪♥r 20K ❬❪❩♥ ❬❪

sts ♦r ♦♦ s②st♠s s t♦rt ♣rt♦♥s ② ❩♥t rst♥ r♦♠ t t♦♥s ♠② ♦rst♠t s tt♦rs ♦ ♥♦t ♥ ♥tr rs♦♥♥t stts ♥ t ♠♥♦rt② ♥♥ s st♦♥

r♦♣ ♣r♦t tMgO rrr t r❬❪ ❬Ωµm2❪ ❬❱❪ ❬♥♠❪

❨s 20K 20K ❬❪❩♥ ❬❪

sts ♦r ♦♦ s②st♠s s t♦rt ♣rt♦♥s ② ❩♥ t rst♥ r♦♠ t t♦♥s ♠② ♦rst♠t s tt♦rs ♦ ♥♦t ♥ ♥tr rs♦♥♥t stts ♥ t ♠♥♦rt② ♥♥ s st♦♥

r ♦♠♥ ♣♥♥ ♦♥ t ♣r♦t ♦r r♦s s♠♥t t♥♥ ♥t♦♥s ①trt r♦♠ ts

♦r♦r rrr ts r♣♦rt s♦ s ♠ ♦r t♥ ①♣t r♦♠ ♥ t♦ t s ♥♦♥ tt t ♥♣ ♦ t t♥ ♠ ♥st♦r ♥

Page 64: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P

♦r t♥ ♦ ts ♦♥tr♣rt t♦ ♥t s③ ts ❬❪ t r♣♦rt sr st sr♣rs♥② ♦ r s♠♠r③s t ♥r ♣♥♥ ♦♥t rsst♥r ♣r♦t ♥t t♥♥ ♥t♦♥s t ♣r♦t ♦s t♦103µΩ♠2 s♠ t♦ s♦ s♦♠t r s ♦st ♦ t♠ ♥♦r♣♦rt♦ tr♦s ❲ rr t♦ t r♣ ♣r♦r♠♥ ♥②ss ♦ ♦r rsts♥ st♦♥

r r t ♦r ①♣r♠♥t②♦sr t ♥r② s ♦ t 2 ♥ r3 s②st♠s st t♥ ts tss r t ♥②sss ♣r♦r♠ ♥ t t①t ♥r② ♣s r ♥ ♦♥ t rt s ♦ ♣tr♥ t s②♠♠trs ♦ ♥ ♥ ♦♥t♦♥ ♥s ♦ ♥ ♦ rs♣t②❬ ❪

♥r② ♣♦st♦♥s ♦ rt♥ ♥♦♥ t s ♥ t ♥ ♣ ♦ st trs r s♠t② s♦♥ ♦r r②sts ♥ s ♥ ♠♣♦rt♥t♥♦t t t②♣ ♥ ♥st② ♦ ts ♥ t t ♣♥♥♥ str♥t ♦ t r♥trt② ♥ ts tr t t rrr ts tr rt t♦ tst s ♦r t♦ t ♦♥t♦♥♥ ♥ s rtr♠♦r s t ♣rs♥♦ ts t♥ t ♥r② ♣ ♥tr♦s t♦♥ ♥♥s ♦ tr♦♥ tr♥sr t② ♠② tr② ♣r♦ ♦r♦r t r②st♥ s♠♦♥t♥s②st♠ ♦♠s ①♣♦s t♦ t t ♦ ♥ ♣♣r♦♣rt ♥t ♥ s♦r♣t♦♥ ♦rs ♦♥ ts sts rst♥ ♥ ♥ ①t stt ♦♥st r①t♦♥ ♦ ts②st♠ s t♦ ♥ ♠ss♦♥ ♦ ♣♦t♦♥s t ♦rrs♣♦♥♥ ♥rs s sststt ♦t s♦r♣t♦♥ ♥ ♠ss♦♥ s♣tr ♠② ss♥t ♥♦r♠t♦♥ ♦t t♥tt② ♥ ♥st② ♦ t strtr ts s♠t rs s♦ tt♦♣♥ ♦ ts ♥st♦rs ♠② s♦ t♦ t ♣♣r♥ ♦ rt♥ ♥r② s

t ♦ ♥t t♥ ts st② t♦ t ♥t♦ ♦♥t rt♦♥s ♥ rrr t♥ss t ts t♥ss s t st ♥♦♠♥ ♥ t s ♥②t② t t♦ ♦♥sr t rrr t♥ rrr t♥ss ♣r♠trs ♥tr ♥t♦ t ♣r♦t s♣rt②

Page 65: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❯ P

ts ♦♥ ♦♣♥ ♦ ts ♠trs ♥ ♦rr t♦ ♦t♥ t♦♥ ♥t♦♥ts r①t♥s② ♣r♦r♠ ♦r ♦r ♦♣♥ ♥♦t rss t st①♣t② t♥ ts tss rtr ♠s t♦ ♥ ♣r ♥sts ♥t♦ ts♦ t tr ♠tr① rtr t♥ ts rst♥ r♦♠ ①♣t ♦♣♥ts

❲t♥ ts tss tr② t♦ rt t ♦ t rrr ts t♦ ♦rrs♣♦♥♥ strtr ts ♥ t r②st♥ rrrs ①t t♦ r♣♦rt rrrts ♥ t ♦ ts ♣r♦♣♦s ♣♦ss ♦rrs♣♦♥♥ t t②♣s rs♣♦♥s ♦r t s ♦sr t s ♥ ♣♦ss tt rrr ts ♦ ❱r♣♦rt ② r♦♣s ♦ ♦♦r ❬❪ ♥ ❨s ❬❪ s s ❱ ♦sr ② tr♦♣ ♦ Pr♥ ❬❪ ♦rrs♣♦♥ t♦ t♥♥♥ t ♥trs ♦ F2 ♥ FF+ t②♣rs♣t② ♣r♦♣rts ♦ ts t sts ①♣♥ ♥ t ♦♦♥sst♦♥

♣t tt② ♥ r②st♥ s②st♠s

♥s♠ ♦①

r ♠t r♣rs♥tt♦♥ ♦ r②st♥ tt ♥s ♦♥ ttr ♥♦♠♥tr ❲t t♦♠s r t♦♠s ♦♥s ♣t ❬❪

♠♦♥♦r②st s ♦♠♣♦s ♦ tr♥t♥ ♥ t♦♠s s ♣r♦s②s♦♥ ♦♥ ❱♥s t♥ t r②st♥ tt ♥ r♦♣ s s♥

Page 66: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P

♦①②♥ ♦r ♠♥s♠ ♥s F ♥ V ♥trs rs♣t② ♦①②♥ ♥s ♥♠ F2 ♦r M ♥ ♥♦r♥ ♦①②♥♠♥s♠ ♥s ♠rs P ❬❪ r ♦♠tr ♣♦st♦♥ t♥ t r②st s s♠t② s♦♥ ♦♥

t ♦r♠t♦♥ ♥r② ❬❱❪F F+ F 2+ F2M V V − V 2− P

t ♦r♠t♦♥ ♥rs ♥ r②sts s♣rsr♣ts♥♦t t ♥r② rqr t♦ r♠♦ ♥ t♦♠ t♦ t♦♠s ♠♥s t ♦s♥r② t t ♥r② ♣r ♦r♠ ♥t ❬❪

F ♥ V ♥trs ♠② ①st ♥ tr ♥tr stts s s ♥ t r ♦r♦② r rtt♥ F+ F 2+ V − V 2− ♥ s ♦ t F ♥ V ♥trst ♦r♠t♦♥ ♥rs ♦ t ts r ♣rs♥t ♥ t s trt♦♥ ♦ F t s ♥rt② ♠♦r ♦r t♥ tt ♦ M t ♣rs♥ ♦ ts t♦♥ stts ♥ t r②st rts t♦♥ ♥r② st♥ t ♠♥♠♠ ♦ t ♦♥t♦♥ ♥ ♥ ♠①♠♠ ♦ t ♥♥ ❱

t♦♥s ♦ t ♦r♠t♦♥ ♥rs ♦ t ts ts s s tr♣♦st♦♥ t♥ t ♥r② ♣ ♥ ①t♥s② st s s♦♥ ② ♦s♥tt t F ♥ F+ ♥trs ♦s t♦ t ♠ ♦ t rrr ♥♣❬❪ s ♦ r ♠♣♦rt♥ s t ts ♥ ♦♣t② st t t♦ ♥r② ♣♣r♦①♠t② tt ♦ t ❱ ♥♣ ♥♠ ♦ t sr♠♥ts t ♥ t s ♦ ♥t ♦r t ♠sr♠♥t t♦ ♣r♦r♠♥ ♠ ♥ ♦rr t♦ ♦ ♥t♥s ♦♣t tt② ♦ t t♠♦s♣r

♥t② ❯♥ ♥ ❯♥♦ ♣s t ♥②ss ♦ t t♠rs♦♣♦t♦♠♥s♥ r♦♠ t s②st♠ s♣② rr♥ t F ♥ F+ ♥trs❬❪ ♦♣t s♦r♣t♦♥ ♦♥ ♦t t t②♣s ♦rs t ♥♠ ❱ ♦r F♥ ♥♠ ❱ ♦r F+ ♥tr s② ♦sr s t ♦♥♦t ♣ r♦♥♥♠ ♥ s s♠ r♥ tr ①tt♦♥ s② ♦rs s♠t♥♦s②❬❪

s♠t r♣rs♥tt♦♥ ♦ t F+ s♦r♣t♦♥ st② s s♠t② r♥♦♥ ♥ s r② sr ♦ ♦r t ♦♠♣t ♥②ss ♦♥ s♦ rrt♦ t rt

Page 67: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❯ P

r t♠rs♦ ♠♦ ♦ ♥ts rt t♦ s♦r♣t♦♥ ♦ ♣♦t♦♥ t F+

♥tr r♦♥ stt ♦ F+ ①tstt ♠ss♦♥stt t F+ ♥tr ①t t♦ r♦♠♥t♦♥ t r tr♦♥ r♦♠t ♦♥t♦♥ ♥ ♦t t ♥ts ♦r r♦♠ t t♦ rt ♦♥ t t♠s ❬❪

s♦r♣t♦♥ ♣r♦ss ♥♦s ♥♠ ♣♦t♦♥ tt s s♦r t t r♦♥stt ♦ t F+ ♥tr ♥ ♣r♦♠♦t t♦ t ①tstt ♥tr ♠② q② tr♠③ rt② t♦ t ♠ss♦♥stt ♥ ♠t t ♣♦t♦♥ ♦r ♦♠ s♦rt② tr♣♣ ♦r ts r①t♦♥ rsts ♥ ② ♠ss♦♥♦r t tt♦♥ ♥r② s ♠ s♠r t♥ tt ♦ t t♦ ♠♥t♦♥♣r♦sss t ♠② tr♠② ♦♥③ r♦♠ ts ①t stt ♥ rs t tr♦♥t♦ t ♦♥t♦♥ ♥ ♥ t r F 2+ ♥tr rs tr♦♥ ♥ t♥♥tr♦ t s♦ tr♣s ② tr♠②♥ tr♣♣♥ ♥ rs♥ ♥t②t tr♦♥ r♦♠♥s t t F 2+ ♥tr rst♥ ♥ ♦r♠t♦♥ ♦ t ①t F+

♥tr ♥ tr♥ r①s t♦ ts r♥ ♦r♠ ♥ ♠ts ♣♦t♦♥ s ♠ss♦♥♦ ♦sr ♥ t t♠rs♦ s♣tr♦s♦♣② t♥ t ♠s♦♥ t♠s

qt♦♥ sr♥ t s♦r♣t♦♥ ♥ ♦ ♥ts ♦♥ t t rst♥♠tt ♣♦t♦♥ ♥rs ♦r t F+ ♥tr s♦r♣t♦♥ ♦r s♥r♦s ♥ ♠② rtt♥ s ♥ t ①t stt ♦ t rs♣t ♥tr

Page 68: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P

F+ + hν(250nm) → F+∗

F+∗ → F+ + hν(390nm)

❲rs ♦r t r s♥r♦ ♥ t tr♦♥ s rs t♦ t ♦♥t♦♥♥

F+ + hν(250nm) → F+∗

F+∗ + kT → F 2+ + e−

F 2+ + e− → F+∗

F+∗ → F+ + hν(390nm)

tr s♥r♦s t♦ ♠ss♦♥ ♦ t ♥♠ ♣♦t♦♥ s♠r s♠ ♣♣s t♦ s♦r♣t♦♥ ♦♥ t F ♥tr t ♥♦ ♠ss♦♥ t♥

t ♥st♦µs t♠ r♦♥ s ♦sr ssts tt ♠♦st ♦ t ①t F♥trs s② ♦♥③ ② ♣r♦♠♦t♥ ♥ tr♦♥ t♦ t ♦♥t♦♥ ♥ t♦ r②s♠ tr♠ tt♦♥ ♥r② ts ♦♠♥ F+ ♥trs

qt♦♥ sr♥ t F ♠♥s♥ ♥ rtt♥ s ♦♦s

F + hν(250nm) → F ∗

F ∗ + kT → F+ + e−kbT≈0

F+ + e− → F ∗

F ∗ → F + hν(≈ 500nm)

♠ss♦♥ ♣ ♦ t ♣♦t♦♥ rst♥ r♦♠ t s♦r♣t♦♥ ♦♥ t F ♥trs r♣♦rt t♥ ♥♠ ❱ ♥ ♥♠ ❱ ❬❪

F+ ♥trs ♠② ♦♥sr s s♦ tr♦♥ tr♣s s ♥ rrs ♦♥③t♦♥ ♦ t F+ ♥tr rsts ♥ rt♦♥ ♦ t F ∗ ♥tr t ①ttr♦♥ ♠② ♣r♦♠♦t t♦ t ♦♥t♦♥ ♥ ♥ t♦ t r② s♠ ♥r②♥ ❯♥ ♥ ❯♥♦ ♦♥ tt ② ♦♣ s♥♥② F t②♣♥tr ♣rs ♠♥♥ ♥♦t F2 ♦r F+

2 t rtr F F+ F+F F+F+ ♣rs♠② ♦♥trt t♦ tr♠② ssst t♥♥♥ t t sts ♥ t ♦tr♥ t F+

2 ♥ F 2+2 ♥trs r ♦♥sr t♦ s ♣ tr♦♥ tr♣s s

t ♥rs ♦ t rts ♦ t ①t ♥s t♥ t♦ ♦r ❬❪♦s♥tt t s♦ tt t ①t tr♦♥s ♠② s♦ tr♣♣ t s♦

②r ♦♥s − ♦s t♦ t ♦♥t♦♥ ♥ ♠♥♠♠ s − ♥trs rstr♦♠ t s♥ ②r♦♥ tr♣♣ ② t F ♥trs ♠r② t♦ tr♣♣♥ t tsts ♠♥t♦♥ ♦r t ② ♥ t ♠♥s♥ ♣r♦♣♦rt♦♥ t♦ t♦♥♥trt♦♥ ♦ t♦s tr♣s t♥ t rrr t♦rs s♦ s♦ tt t

Page 69: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❯ P

♠♥s♥ s t♦♥② ♥♥ ② ♥ tr♦♥ ①tt♦♥ r♦♠ t ♥♥ ♥t♦ t ♠♣t② r♦♥ F 2+ ♦r ①t F+ ♥trs rst♥ rs♣t② ♥r♦♥ F+ ♥ ①t F ♥trs ♦t ♦ ♥t② r♦♠♥ t♦ F ♥trs②♥ t F t②♣ ♠♥s♥ ❬❪

t♣ t♦rt sts sr t ♥r② s ♦ r♥t t②♣s ♦ ts♥♦t② F2 ♦r M ♥tr ♥ r ♥trs ❬❪ ♦r ♠♥s♠ ♥s V♥trs ❬❪ sts ♦ ts t♦♥s r s♠t② s♦♥ ♦♥

tr♦♥t♠ tt♥t

♣t sts ♦ r②sts r sr t♦ ♣r♦r♠ t♦ t ♦r ♥♣ ♦❱ ❬❪ t②♥ ♠tr t ♣♦t♦♥ ♥r② ♦r t♥ ❱ ♦s t♦♦ ♣ tr♦t s♦r♣t♦♥ ② r s tt t ①♣r♠♥t st♣ s rt②s♠♣ ♥ ts s♥s r②sts r ♠♦r ♦♣t② ss

t s ♥♦♥ tt ♣r♦♣rts ♦ r3 str♦♥② ♣♥ ♦♥ ts st♦♦♠tr② s♣② ♦♥ t ♦①②♥ s♣s ♦①②♥ ♥② s r tr♠♥ t♦ ♦r♠t ❱ ♦ t ♦♥t♦♥ ♥ ❬❪ s♦ r② tt ♥r② s ♥ ♥ ♦rrt♦ ♦♥③ s sts ♥ ♣r♦♠♦t t tr♦♥ t♦ t ♦♥t♦♥ ♥ ♦r♦r t♥② ♥ ♥ t ♦tr r ♦r ♥s ♦r♠♥ t strs ❬❪s ts ♦♠♥ t t ♦ ♥♣ rst ♥ ♠ ♠♦r ♥♥t♣♦t♦♠♥s♥ ♦♠♣r♥ t♦

r ♠t ♣tr ♦ t ♠♥s♥ tr s♦r♣t♦♥ ♦ ♣♦t♦♥r♣♣♥ ♦ tr♦♥♦ ♣♦r♦♥ ♦r♠t♦♥ ② ♦r♠t♦♥ ♦ str♣♣ ①t♦♥ tr♥t rt ♦r♠t♦♥ ❬❪

Page 70: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P

t♠rs♦s♣tr♦s♦♣②s ♠♦ sr♥ t ♠♥s♥ r♦♠ s ♣rs♥t ② ♦♥ ♥ r♥r t s s♦♥ tt t♦ ♣♦t♦♥ s♦r♣t♦♥ ♥ tr♦♥ ♠② ♣r♦♠♦t r♦♠ t ♥ ♥ t♦ t♦♥t♦♥ ♥ ♥ ♦r♠ s♠ ♣♦r♦♥ ♦ tt ♣♦r③t♦♥ ♥ ♦r♠t♦♥ r♦♥ t r rrr ♣♦r♦♥ ♥trts t ♦ tr♣♣ ♥r r②st t ♦r ♥ ♠♣rt② ♥ ♦r♠s str♣♣ ①t♦♥ ♦s tr♦♠♥t♦♥ rsts ♥ ② ♠♥s♥ s ♣♦t♦♠♥s♥♠♥s♠ s ♦t♥ ♦sr r♦♠ ♦♠♣♦♥s ♦♥t♥♥ tt♥t ♦tr ❬❪

r ♠t r♣rs♥tt♦♥ ♦ r♦♠♥t♦♥ ♣r♦sss t♥ ♦♥t♦♥ tr♦♥s ♥ ①t ♦s r♦♦♠ t♠♣rtr ♠♥s♥ ①t ♦s♥ tr♦♥s ♥ t str♣♣ ①t stt ♦♣ ♦r ①t tr♦♥s ♥ ①t ♦s tr♦ t s♦ t r♥ ♥ ♥s ♣t t ♣♥ ♥ ♦♥t♦♥ ♥s rs♣t② ❲t ♥ r② rs st♥rs♣t② ♦r ①t ♦s ①t tr♦♥s ♥ ♦♣ tr♦♥s ♥ t ♥❬❪

♥ ♦ t ♠♦r ♣r♦♠♥♥t rsts s ♣s ② ♥ t ❬❪ ♦ rt♦①②♥♥t s♠♣s s♥ t r+ rrt♦♥ ♥ ♦♠♣r tr ♣r♦♣rts t t ♣r str♦♥t♠ tt♥t r②sts ② ♦♥ tt t r3 ♠t♦r ♣♣rs ♥ tr rt② s♠ ♦s ♦ rt♦♥ t② ttrtt♦ t rt♦♥ ♦ ♦①②♥ ♥s ♦♥tt② tt ♣♣rs strts t♦strt s t rrt♦♥ t♠ ♥rss t s ♦♠♣♥ ② t rs♣t ♣♣r♥ ♥ strt♦♥ ♦ t ♥♠ ❱ ♠♥s♥ ♣ ♦sr tr♦♦♠ t♠♣rtr s♠ ♣ s ♦sr ♥ ♦r♥② ♦①②♥♥t r3

②rs rts t ♣♦t♦♠♥s♥ tr rt② t♦ t ♦①②♥ ♥ss ♠♥s♥ rsts r♦♠ r♦♠♥t♦♥ ♦ ♦♥t♦♥ tr♦♥s t ①t

Page 71: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❯ P

r ♠♣rtr ♣♥♥ ♦ t ♣♦t♦♠♥s♥ s♣tr ♦t♥ r♦♠r+ rrt r3 r②sts tr ♥♠ sr ♠ ①tt♦♥ ❬❪

♦s ♠♣rtr♣♥♥t ♣♦t♦♠♥s♥ ♠sr♠♥ts ♦♥ t r+ rrt

r3 s♦ tt t t♠♣rtr rss t ♥t♥st② ♦ t ♥♠ ♥r② ♥rss r♥ ts ♠①♠♠ t tr t strts t♦ s♣♣r♥ t♦ ♣s t ♥♠ ❱ ♥ ♥♠ ❱ ♥ t♦ rs

r♥ ♥♠ ♣ rsts r♦♠ t ♦r♠♥t♦♥ r♦♠♥t♦♥ ♦ ①t♦s ♥ tr♦♥s ♥ str♣♣ ①t♦♥ stts ♥ s ♦♠♠♦♥② ♦sr ♥ ♥t st♦♦♠tr r②sts ❬❪

Page 72: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P

♥rr♦ t ♥t♥s ♥♠ ❱ ♣ s ♥♦t ♦sr ♥ t st♦♦♠trr3 s♦ t s s♣♣♦s t♦ rt t♦ t ♦①②♥ ♥② sts s ts ♥r②s ss t♥ ❱ ♦r t♥ t ♥ ♣ ♦ t t s♦ rst r♦♠ tr♦♠♥t♦♥ ♦ tr♦♥s t ♦s tr♦ r② s♦ t s

t♥♠ ♦①

❨t ♥♦tr st ♦ ts r ♦sr t♥ t 2 r②sts s♣t ①t♥sst② ♦ ♣r♦♣rts t ♠tr qrs ♣♦♥ ♦♣♥ ❬❪ rsr ♦♥ ts♥ ts ♥♦♣ ♠tr① r♠♥ rt② sr ♥r r♥t ♣♣r♦①♠t♦♥t♦♥s ♣r♦r♠ ② s♦r♦♥ t ❬❪ ♦♥ ♥ts 2r tt♥tr ♥s ♦ ♦t tt♥♠ ♥ ♦①②♥ ♥tr♦s ♣ stts ♥ t ♣ t♦ ❱ ♦ t ♦♥t♦♥ ♥ tt ♥♥♦t ♦♥③ s②

r t ♦ ♥st② ♦ stts ♦r ♥tr ♥s ♦ ♦①②♥ tt♥♠ ❬❪

♥tr sss

♦t ♦♥② ts ♥ ♠♣♦rt♥t ♠♣t ♦♥ t s♣♥♣♦r③ tr♥s♣♦rts s♦♥ ♥ t ♣r♦s ♣tr ♣rt r♦♠ t ② rts ♦r s♣ tr♦♥s②♠♠trs t♥ t rrr r ♥♥ ② t stts t s♥ ♥ r②st♥ t♥♥♥ s②st♠s ♣♥s ♦♥ ♦♥ ♠♦r t♦r t t②♣♦ s②♠♠tr② stts t♥ t tr♦ tt r ♥t ♥t♦ t ♥st♦r ♥

Page 73: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

t t② ♦ t ♦♥trtr♦ t♦ ♦t t♠ rs t♥ t strtrtt ♥sr t ♦rrt ♠t♥ ♦ t tr♦♥ s②♠♠trs r♦♠ t ♦♥t♦♥r♠ t♥ t tr♦ t♦ t t♥♥♥ r♠ r♦ss t trt♥ trr t ♥trs ♦r♠r ♣tr sr ♠♥s ♥ ts ♣r♦sss♥ s②st♠s s st♦♥ ♣rs♥ts ♠♣t ♦ ♥tr ♠♣rt♦♥s ♦♥ ts♣♥♣♦r③ tr♥s♣♦rt

①t♦♥

ts ♦♥♥trt ♦♥ t rrr s sr ♥ st♦♥ ♥①t♥s② st ♥ tr♠s ♦ ts ♥tr sss ts ♥tr tt ♠t♥s r ♦r t ♦r♥t tr♦♥s ♥t♦♥ ♥t♦ t rrr s ①♣♥t♥ t ①♣r♠♥t st♦♥ ♦ ts tss t ♣rt ♥tr s ♥♦ts② t♦ ♦t♥ t♦ rs ♦ ♦①t♦♥ s s ♣rtr② tr ♦r t ♦r ♥tr ①♣♦s♥ t ♦r tr♦ t♦ ♥② ♦①②♥ ss t♦♣♠♦st ♠♦♥♦②rs t♦ ♦①③ ♥ ♦r♠ t r♦♥ ♦① ②r t t ♥tr rst♥ ♥t s②st♠ ♥♦tr rs♦♥ ♦r t ②r ♣♣r♥ s t♦①②♥ ♥trs♦♥ r♦♠ ♥t♦ ♥tr ②rs ♦ t tr♦

r ♥tr ∆1 s②♠♠tr② t t r♠ ♥ t ♠♦rt② s♣♥♥♥ ♦r ♥tr t♦t t ♥ t rt t ②r ♦r♠t♦♥ t♦ t ♦①t♦♥ ❬❪

s t ② ❩♥ t ❬❪ t t ♥tr t ∆1 sttst② ♦♣ t♦ t ∆1 ♥s♥ stts ♥ t k‖ = 0 rt♦♥ rst♥♥ ♦r♥t t♥♥♥ ♦ ts stts tr♦ t rrr ♦r ♥ t♣rs♥ ♦ ♥ ♦♥ ♠♦♥♦②r t ♥st② ♦ stts t t ♥tr r♦♥s rst② r rst♥ ♥ t ∆1 t♦ ♥t♦♥ ②r③t♦♥tt s ♠ ss t t♦ t 2p ♦rt ♥tr ♦①②♥sts ♦♠♥t t t♥♥♥ ♥st② ♦ stts t♥ ♥ ♦① ❬❪ ♦r s

Page 74: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P

r ♦r k‖ ♥ t♦t t ♥ t rt r♦♥ ♦①②r t t ♦r ♥tr ♣♥ sqrs ♦rrs♣♦♥ t♦ t ♠♥s♠ ♦r r♦♥s♣rs ♥ t ♦r rs♣t② r♦sss r② s ♦s t♦ t rs♦♥♥t t t ♥ r ♦♥trt♦♥s r♦♠ t s♣rs rs ♦♥♥tt t ♥ r s♠♠ ♣ ♦♥trt♦♥s r♦♠ ♦t ❬❪

t ♦①②♥ st ♥t♦♥ s②♠♠tr② ♦ t ②r s r② r♥t r♦♠ tt♦ t 3d ♥t♦♥♥ ♥tr ♦ ♦♥t♦♥ ♥ ♥ tr♥st♦♥ ♠t ♦①s❬❪ ♦r♥t tr♥s♣♦rt r♦ss t rrr s rst② s♣♣rss

r rst♣r♥♣ st② ♦ t♥♥♥ ♥st② ♦ stts ♥ ♣r ♦♥rt♦♥ ♦ s②st♠ ♦r k‖ t ♠♦♥♦②r ♥srt ♥ ♦r♠t♦♥ t t ♥tr ❬❪

♥ ♣♦sst② ♦ ♦♥ t ♣♣r♥ ♦ t ♥sr ♥tr ②rs t ♥tr♦t♦♥ ♦ t ②r t♦♣ t ♦r tr♦ ❬❪ ♥♣♥ tt s ① ♦♥ t r♦♥ tr♦ tt ♦♥st♥t ♥sr♥♣t① ♠t♥ ♦ t ②rs ♥s♠ s st ♦①③♥ ♠♥t ♠② s♦r♦①②♥ ♥ ♦r♠ ♥ t♦♥ ②r s ♦ ♦ t ♦①②♥ s♦♥♥t♦ t r♦♥ ♥ ♣r♥t t ♦r♠t♦♥ ♦ t r♦♥ ♦① s s♦♥ ② ❲♥ t

Page 75: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

t ♣rs♥ ♦ t ♥tr ②r ♦①③ ♦r ♥♦t ♦s ♥♦t tr t♥t♦♥ rsst♥ s♥♥t② t t ♠② ♥♥ t tr♥s♣♦rt ♣r♦♣rts s t♣rsrs t ∆1 tr♥s♠ss♦♥ ♥ t P ♦♥rt♦♥ t ♥♦♥♣rrr ∆2′

♥ ∆5 s②♠♠trs ①st ♦r ♦t P ♥ P ♦♥rt♦♥s ② t♥t ♠♥s♠ ②r r♣②

♦♥sq♥s ♦ ♥♥♥

♥tr ♦① ②r ♦r♠t♦♥

t s ♥♦♥ tt ♣♣r♥ ♦ t ♥tr ♦① rrr ♠② s ♦♥sq♥ ♦ ♥♥♥ ♦ t st s t t♠♣rtr ♦♦sts t ♦①②♥ ♠rt♦♥r♦♠ t rrr t♦rs t tr♦s sts r s♦ ♣r♦r♠ t♥t t♠r♠ ♦ ts tss ♥ t ♥♥♥ ♠♣t ♦♥ ♣r♦♣rts ♣rs♥t ♥ st♦♥ ♣rs♥ ♦ s♣ ♦①s s rt② rt t♦ tr♦r♠t♦♥ ♥t♣② s t ♦r ♥ t♦ ♥♥♥ s rr s trr ♦r t ♥tr ♦① ♦r♠t♦♥ sts ♣r♦r♠ ② ♥♠r t s♦ tt ♥ s♦♠ ss r t ♦ t ♥♥♥ ♣r♦ss ♠②r t ♥tr r♦♥ ♦① ②r ② t s♦♥ t♦rs t ♦ ttr♦ ❬❪

① ♦r♠t♦♥ ♥t♣② ♠♦23 2 r ♦

♦r♠t♦♥ ♥t♣② ♦ st ♦①s ❬❪

s♦♥ ♦ ♠trs ♠♦♥ t ②rs

t♥♦♦② rqr ♣rs♥ ♦ ♦r♦♥ ♥ ♦ tr♦s ♥ t ♥♦ tr ♥♥♥ s rs t♦ ♥ t♦♥ ♥trrt qst♦♥ r r♦♥trt♥ ①♣r♠♥t r♣♦rts tr r♥ ♥♥♥ ♦ t st t ♦r♦♥t♦♠s s t♦rs t ♦ t tr♦ ♦r ♥ t rt♦♥ ♦ t ♥tr❬❪ rt♦♥ t s ♥t♦ t♦♥s t♦ s♦ tt t s t ttr s tts rs t♦ t s♠r ♥♥ ♦ t ♥t♦♥ ②r③t♦♥ s ♥ s ♦ t ♣♣r♥ ♦♠♣r t ♥ t ♦tr ♥ s♦♠ r♦♣ss♦ tt t ♦r♦♥ s♦♥ ♥t♦ t rrr rsts ♥ t ♦r♠t♦♥ ♦s ♥♦t s♣♣rss t rt♦ s♥♥t② ❬❪ ♦r ①♠♣ ♥ t

Page 76: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P

r ②r ♣r♦t ♣r♦t② ♥st② ♦r ∆1 s②♠♠tr② ♥ t ♠♦rt②s♣♥t F ♦r t ♦ tr♠♥t ♥tr ❲t ♥ rs ♥♦t s♥ ♥♣rs♥ ♦ ♦r♦♥ rs♣t② ♥tr ♦r♦♥ ♦r s ♦r t♦♥ss s♣r ♦s♥ s ♠♦♥♦②rs ♦r ♥ ♦ ❬❪

s♦ tt ♦r♦♥ s♦♥ ♥t♦ t rrr r♥ ♥♥♥ ♦r♠s t st♦♦♠tr23 ♦s ♥♦t rt ♥② ♠♣ stts ♥ t rrr t rs t rrrt t ♥rs♥ ♦♥♥trt♦♥ ♦ ❬❪

♥♥♥ t♠♣rtr s t ② ♣r♠tr t♦ ♦t♥ ♦rrt② r②st③ ②♥ ♥t♦♥s s s♦♥ ② rt t ❬❪ ♥♥♥ ♦ s t♦ t s♦♥ ♦ t♦♠s r♦♠ ♦tr ②rs ♥t♦ t rrr ♥ ♦ss ♦ t♦ t①tr strtr ♥ t ♦tt♦♠ ♦ tr♦ ♦r♦r s t♠♣rtr ♥♥♥ s t♦ t s♦♥ ♦ ♠tr r♦♠ t ②r ♠♦st②♥ ♥t♦ t rrr rsts ♥ sst♦♦♠tr② ♦ t ♦r♠r ②♥ tsr ♣♥♥♥ str♥t ♣♣r♥ ♦ t s ♠tr t♥ t rrrs♦ s♥♥t② ts t rt♦ ❬❪ ♥ t ♦tr ♥ r♥t①♣r♠♥ts ② rs♦♥ t s♦ tt ♥♥♥ t ♣ t♦ ♦s ♥♦t s t♥ s♦♥ r♦♠ t ②r ♥t♦ t rrr t rtr ts srt♦♥ t t♥tr ♦s ♥♦t tr t s♥ rt② ❬❪

❯♥rt♥ ♥tr tr♠♥t♦♥

trs ♦♠♣♦s ♦ tr♥t♥ ♣♥s ♣rs♥t ②t ♥♦tr ♥ rr♥t ♥tr qt② ♥ s ♦ r3 t ♥tr 2 tr♠♥t♦♥ st t♦ ♠♦r ♥rt② ♦r t♥ t ♦♥ ♦ t r ❬❪ ♦r

Page 77: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

r ♥♥♥ ♠♣t ♦♥ t rt♦ ♦ ♥♥♥ t ♦r r♥t t♠ rt♦♥s ♥ r♥t t♠♣rtrs ♥ t♠s ♦ ♥♥♥ strtr st s♦r♥♦♦♦ ♦r③♦♥t ♥ ♦♥ r t ♠rs t rt♦ ♣t ♦r ♣rt♣♣t♦♥s ❬❪

r rss ♣♣ ♦t t ♦r 2 t ♥ r rt tr♠♥t ♦ ♥tr ♥ ♦ ♥t♦♥s ♦ tr♥s r♣rs♥tt r♦♠ ❱ rs ♦♣♥ rs rr t♦ ♠♥t s♣s t ♥ s r r♣ s♦s t ♦r t♦ r♥t ♥t♦♥s ❬❪

t ♥rt♥t② ♦ ts ②r s r ♠♣t ♦♥ t ♦r ♦ t s②st♠ts ♣r♦r♠ ♦♥ ♦ s②st♠s ② ❱r r♥ t s♦ tt♣♥♥ ♦♥ t tr♠♥t♦♥ ②r t ♠♥t♦rsst♥ ♠② ♥ stts s♥ sst♥ tt t ♠① 2 ♥ r ♥tr ♦ ② t♦t ♥ ♥ r ♦ ♦t ♣♦st ♥ ♥t ♦♠♣♦♥♥ts ♦♦s②

Page 78: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P

♠ ♦r t♥ ①♣t ② s♦ ♥ tt t t s str♦♥② t ② t♥tr ♦①②♥ ♦♥♥trt♦♥ ❬❪

tr♦♠rt♦♥ ♥ srt♥

♥ s ♦ ♣rt ♣t① s②st♠s t ♠♦♠♥t♠ tr♥sr t♥ ♣r♦♣t♥tr♦♥s ♥ t♦♠s ♦r♠♥ t r②st ♥t♦r s ♥ s tt t tr♦♥♥t♦♥ s②♠♠tr② s ♦♥sr ♦r t s②♠♠tr② s ♥♦t ♦♥sr tr♥ ♦♥rs ♥ ts t♥ tts ♦ ♦t ♠t ♥ ♥st♦r t s tts ♣s tt t ♦♥♥ ♥r② ♦ t♦♠s s ♠ ♦r t♥ ♥ t ♣rtr②st rsts ♥ t tr♥sr ♦ ♠♦♠♥t♠ ♦ ♣r♦♣t♥ tr♦♥ t♦♥ ♦♥ ♥ tr♥ ②s ♦r t♥ t ♥ t rt♦♥ ♦ tr♦♥ ♦s ts ♦r rss t♦ t ♦♠r♠♥t ② tr♦♥s t ♠② ♦♠ s♥t♥♦ t♦ ♦r♦♠ t ♦♥♥ ♥r② ♦ t ♦♥ ♥ r♦t t s rt ♦t♦♠s t♥ t ♠tr s tr♦♠rt♦♥ ♣♥♦♠♥♦♥ s s♣②♣r♦♥♦♥ ♥ rr♥t ♥sts ♦ tr♦ t ♠tr s tr ♥s ♦ ♠r♦♠trs③ ♠♥t t♥♥ ♥t♦♥s tr♥s♣♦rt ♦ t ♠trs r ♦r ♦t ♥ ♥tr r♦♥s ♦ ♥t♦♥s ♦r ①♠♣ t s♥♦♥ tt t tr♦♠rt♦♥ ss rstrt♦♥ ♦ ♦①②♥ ♥s t♥♣r♦sts ❬❪

tr♠ ♠♠rst♦r s ♦♥ t♦ sr ♦s rsst♥ ♥ss t ♦♥sq♥ ♦ ♥ ♣♣ rr♥t ♥ ♣rssts tr t rr♥t ♦ st♦♣str♦ t sr Pt2♥♠Pt ♥ ♦ t trrr s ♥t② ♦①②♥♥t ❬❪ ①②♥ ♥s t s r rrrs♠♥♥ tt t ♣t ②r s ♠ ♦r rsst♥ t♥ t st♦♦♠tr♦♥ ❲♥ ♥ tr s ♣♣ ♦①②♥ ♥s ♥ t♦ rt ♥♥t ♦♥r② t♥ ♦t 2 ②rs ♥ ts tr♠s t ♠♠rst♥ t sts

♦♥ t st ♦1−xrx ♥t♦♥s t ① ♥ t♥ ♥ ♥t♦♥s r tr② ♥st ♥ t ♦ t♠♣rtr ♥ sss ♦t ②♥ t♦ rrs ♥ ♥ ♠♣t ♥ s♥ ♦ t t♦rs ♥ ♥ ♥ ♦ r srt♦♥ t♦ t ♦r ♥tr ♥ ts♦①t♦♥ ❬❪ ♥tr ♠♦t♦♥ s sst t♦ t rs♦♥ ♦ ♦ t s♥ ♥rs♦♥ t ♦r s②st♠ rsst♥ ♠② rst r♦♠t ♦r♠t♦♥ ♦ ♥s s ssts ♥ ♣♣r♥ ♦ ♦♥t♥ ♠♥tt♥ t rrr ♦ rst r♦♠ t tr♦♥s tr♣♣♥ t ♦①②♥♥tsts ❬ ❪ ♦sr t s rrs s♦ t srt♥ ♦ ♥t♦♥s② ♣♣②♥ rr rr♥ts ♥ ♦♠ t♦♦ t♦ ♥♥r ♣r♦♣rts ♦ s♦r♦r ts rsts r t rst t♦ ♠♦♥strt t ♣♦sst② ♦ ♥♦r♣♦rt♥♠♠rst♥ ♥ ♠♥t♦rsst♥ t♥ s♥

rsr ♦ ♠♠rst♥ s ♦♣♥ st ♥ s ♠♥② ♥trst♥

Page 79: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

r ♠sr♠♥ts ♦♥ ♦80r20 ♥ ♥ ts r♥stt ♥ tr ssq♥t s rt♥ t♦rs t ♥t ♥ ♣♦strr♥ts ❬❪

rsts ❬❪ ♦ ♦ ♠♥ r ♣r♦r♠ ♥ ①t♥s st② ♦♥rsst st♥ ♥ s s t r ❬ ❪ ♥ ❱ ❬❪ t♥trs ♦r ♥ t ♦ t rrr s r♦♣ ss♠ ♥ ♥trst♥ ②♣♦tsstt t ♠♠rst♥ ♥ ts s②st♠s s ♥ t ♦ r♥ rtr t♥ ♦ ttr♦♠rt♦♥ ❬❪

t♥ ♠♥ts♠

♥t sts s♦ tt t ♣rs♥ ♦ ♥s t♥ r②st♥ ♥st♦rs ♦rs♠♦♥t♦rs ♠② rst ♥ t ♣♣r♥ ♦ ②t ♥♦tr ♣♥♦♠♥♦♥ ♠♥ts♠ s s ♣r♦s② ttrt ①s② t♦ ♥ ①♣t ♦♣♥ ♦ ♠trs ♥ t ss♦t rsr s ♦ t ♠♥t s♠♦♥t♦rs ♥♦①s rt ♥ rs♣t② ❬❪ rst ♦♥ ♠r ♦♥t ♦t♠♣rtr ♥tr♣② t♥ ♠♥t③t♦♥ t①tr ♥ ②♥♠s trrr ♣♦♣t♦♥ ♥ rr♥ts r s♦r ♥ ♥s ♣♥ ♥s♠r strtrs ❬❪ s♦♥ s ♥r② ♥♦ t♦ strt♥ t rst r♣♦rt ♦ t r♦♦♠t♠♣rtr ♠♥ts♠ ♦♥ ♦♦♣ 2 s♣s ② ts♠♦t♦ t ❬❪

♥ r♥t ①♣r♠♥t rt♥③♦t t ♦sr ♥♠ ❱ ♠ss♦♥r♦♠ ♥t r②sts ♦s ② rsts r♦♠ tr♣♣♥ ♦ ♦s t ♠♥s♠ ♥s ❬ ❪ ♠♣s r♦♠ t ♠ss♦♥ ♦rs s♦ ①t

Page 80: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P

r Pr♦t♦♥ ♦ P s♠t♦♥ r♦♥ ♥② ♦r ts ♦①②♥ ♥rst ♥♦r t♦♣ ♠♥s♠ ♥rst ♥♦r ♠ ♥ ♦①②♥ ♥①t♥rst ♥♦r ♦tt♦♠ s♦♥ s ♦♥t♥♦s ♥s ♦♠♣♦s ♥ ♠♦r ♣♦st ♥ ♠♥♦r ♥t ♦♠♣♦♥♥ts s ♥s s♦ rs♣t ♥♦♥s♣♥ ♦♠♣♦s P ♥ s♥ ♦ t ♥② ♥t ♠♦♠♥t ♠♠ ♦ rs♣tt♦♠ s ♥ ♥ ♦r ♠♥t♦♥s Q st♥s ♦r ♣rt t♦♠ r ♥♣♦♣t♦♥ ♥ ♥ |e| ♥ s ♦♠♣r t♦ ts s ♥ ♣r♥tss ❬❪

r♦♦♠t♠♣rtr rr♦♠♥t ♦r ♥ tr♥ rss r♦♠ t s♣♥ ♣♦r③t♦♥ ♦ 2p tr♦♥s ♦ ♦①②♥ t♦♠s r♦♥ ♠♥s♠ ♥s rr♦♠♥t ♦rr♥ s ♠♦st ♥♣♥♥t ♦♥ t s♠♣ t♥ss t♥t ♥♠ r♥ ♦r♦r s♣t t ♠♥t ♣r♦♣rts t r♠♥s tr♥s♣r♥t ♥ t s r♦♥ ♠s t ♥ ♥trst♥ ♥t ♦r♠♥t♦♦♣t ♣♣t♦♥s

♦♥s♦♥s

r♦strtr trs r ♦ r ♠♣♦rt♥ ♦r ♥♦♥♥t♦♥ ♠♥t ♣r♦♣rts ♦ ♦t ♠♥t t♥♥ ♥t♦♥s ♥ tr r②sts s♣t ♠t♣♦♣♥ ①♣r♠♥ts ②♥ ①♥t rsts ♦♥ t ♠♥t s♠♦♥t♦rs♥ ♦①s t ♦♠s r tt t t② t♦ rt ♦♥tr♦ ♥ ♥♥r tstts t♥ t ♦① rrr s ♦ t♠♦st ♠♣♦rt♥ ♦r rtr ♣r♦rss t♥t ♦ s♣♥tr♥ r♦ss ♥♦r♥ ♦①s s s tss ♠s

Page 81: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

r ♦ ♠♥ ♥ r♦♦♠ t♠♣rtr t♦♣t ♥st ♠♥t③t♦♥ ♠sr♠♥ts ♦♥ t♥ ♠s ♦ r♥t t♥ss r♦♥ t♦♣ t r3

sstrts ♥t s ♣♣ ♥ t ♠ ♣♥ t r ♦rrt ♦r♦♥trt♦♥ ♦ t sstrt ♦tt♦♠rt ♥st ♣tr s♦s tt t s♠♣ r♠♥s tr♥s♣r♥t ♥ t s r♦♥ ❬❪

t♦ s♥ t♦♥ t ♦♥ trt sss ♥ ♠♥t t♥♥ ♥t♦♥s ♥♠trs ♦♥ t② r s t t ♦♣ tt t ♠② r ②t s s♣ts ♦ ts strtrs ♥ ♣ t ①t♥s ♦r sts t♦ ♠ rtrst♣

Page 82: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P

Page 83: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

Prt

①♣r♠♥t r③t♦♥

Page 84: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue
Page 85: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♣tr

♠♣ r♦t t♥qs ♥

♦♣♠♥t

s ♣tr srs r♥t r♦t t♥qs s ♥ ♦rr t♦ rt s♠♣sst t♥ t t♠r♠ ♦ ts tss rst st♦♥ r② ♥tr♦st ♣♠♣♥ s②st♠s s ♥ ♦rr t♦ rt ♥ ♠♥t♥ t tr ♠rqr ♦r t sr r♦t ♦ t strtrs s♦♥ st♦♥ srs t♣r♦r ♥ rsts ♦ sstrt ♣r♣rt♦♥ ♦r ②r ②st♠ ♣♦st♦♥t t P s q♣♣ s s②st♠ s ♦♠♣♦s ♦ r♥t ♣♦st♦♥♠rs s♣ttr♥ ♣♦rt♦♥ ♥ ♦r♥ ♠♦r ♠ ♣t①② s♣ttr♥ ♣♦st♦♥ ♠r ♦ ②r ②st♠ s ①t♥s② s ♦rt rt♦♥ ♥ ♦♣t♠③t♦♥ ♦ t r♦t ♦♥t♦♥s ♥ t ♦♥tr♦ ♦ s ♥t♦♥s r r♦♥ t t ♥sttt ♥ ♠♦r ♥ ♥② s rst♦ ♦♦rt♦♥ t ♥ ♦t ♦ ts s♣ttr♥ ♣r♦t♦♦s r ♣rs♥t♥ t tr st♦♥ ♣♦rt♦♥ ♠r ♦ t ②r ②st♠ s t♦ ssr①t♥t s ♦r t s♠♣ ♣♣♥ s♦ ts t♥ ♠ ♣♦st♦♥ s sr ♥ st♦♥♦r r♥ ts tss ♠♥t t♥♥ ♥t♦♥s ♦♥t♥♥ r3 ♥ 2

rrrs r s♦ st s r strtrs ♥♥ 0.7r0.3♥3 tr♦s ♣♦st ② ♣s sr ♣♦st♦♥ P tr♦ ♥ ♥tr♥ P ♦♦rt♦♥t ♦s r♦♠ t ♣rt♠♥t ♠ t s tr① ♥♦r♥qs P ♣♦st♦♥ s sr ♥ t t st♦♥ ♦ ts ♣tr

❯tr ♠ ♣♠♣♥ s②st♠s

♥ ♦rr t♦ rt trt♥ strtrs ♦ qt② t ♣♦st♦♥ s t♦ ♣r♦r♠ ♥ t tr ♠ ❯❱ r♥ ♣rr② ♦ t st −9 ♠r♦rr r♥t♥ ♠♥♠♠ ♣rs♥ ♦ ♥sr ♣rts ♥ t ♠r r♥t r♦t ♦♥ t t st♥r ♠♥ r♦tr② ♣♠♣s tt ② ♣rssrs♦♥ t♦ −3 ♠r ♥♠r ♦ s♣③ ❯❱ t ♣♠♣♥ t♥qsr s t♥ t t♠r♠ ♦ ts tss

Page 86: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P ❲ ❯ ❱P

r♦♠♦r ♣♠♣s ♦♥t♥ r② r♣② ♣ t♦ ③ s♣♥♥♥ r♦t♦rst ♠♦s ♥ ♣rts r♦♠ t ♥t s ♦ t ♣♠♣ ♦ ts r♥ ♠♦♠♥t♠ ♥ rt♦♥ ♦ t ①st s ♣♠♣s r s② s♥ t♦♦♣rt ♦ −2 ♠r ♥ r ♣ t♦ r ♣rssr ♥ t ♠r ♦♥t♦ −9 ♠r r♥

♦♥ ♣♠♣s s tr ♣♦t♥t ♠♦r t♥ ❱ ♥ ♦rr t♦ ♦♥③ss str♦♥ ♠♥t ♥ ② ♣r♠♥♥t ♠♥ts t♥ t s ♦t ♣♠♣ t♥ rts t ♦♥③ s♣s ♥ ♠s t♠ ♥t♦ t s ♦t ♣♠♣ ♦♥ ♣♠♣s ♦ ♥♦t rqr ♥tr ♠♦♥ ♣rts ♥♦r ♦ ts t② r♥♦t ♦♥② r② t rt♦♥r s ❯♥r ♦♥t♦♥s ♦♥ ♣♠♣s r♣ ♦ r♥ ♣rssrs ♥ ♦♥ t♦ −13 ♠r r♥

t♥♠ s♠t♦♥ ♣♠♣s ♦♥t♥ tt♥♠ ♠♥ts r♦♠ t♦♠ss♠t ♦♥ ♣ t♦ rr♥t s ♣♣ t♦ t♠ ♠t tt♥♠s t♥ ♣♦st ♦♥ ♥tr♥ srs ♦ t ♠r ♥ strts t♦ ttrt ♥ tr♣♣rts ♠♦st ♦♠♠♦♥ rt♦♥ s t ttrt♦♥ ♦ ♦①②♥ ♥ t ♦r♠t♦♥♦ s♦ 2 ♥ t♦ t ♣rssr rt♦♥ ♦s② strt♦♥ s r tr rt♥ t♠ s♦ r♣tt tt♥♠ s♠t♦♥s t♦ ♣r♦r♠ ♥ ♦rrt♦ ♥sr ♣rs♥ ♦ ♥ ♥ t ttr ♦♥ ♥tr♥ s ♦ t ♠r r ♦ t tt♥♠ s♠t♦♥ s tt t ♥♥♦t ♣r♦r♠ ♥ rt♥t② ♦ t s♠♣ s ♦ t♦ s♦ ♦ s t t♦♠s t♦ ♥♦r♣♦rt ♥t♦t s♠♣ ♥ r♦♥

♦t ♦ t ♥tr s②st♠ s ♣r♦r♠ t♠ t ♠r s ♦♣♥ ♥①♣♦s t♦ ①tr♥ t♠♦s♣r ♦r♠② ♦♥t♠♥t♦♥ ♥ ♣rts r t♦srs ♥ s ♦r ①t♥ ♣r♦ ♦ t♠ s ♦tss♥ s ♠ str ♥r t♠♣rtr t ♠r ♥s t♦ r♣♣ ♣ t rsst♥ trr ♥ ♦t ♦r ♦ ②s t t♠♣rtr s s r♥t tss s♦ s t♦ rss t ♠♥ ♦♥t♠♥♥t tr t♦♥ ①tr♥♠♥♠ ②r ♦r♥ t ♣rts ♥ ♦t s r♦♠♠♥ ♥ ♦rr t♦♣r♥t t t r♦♠ ss♣t♦♥ ♥t♦ t ♥r♦♥♠♥t

strt ♣r♣rt♦♥

♦ ♥② ♣♦st♦♥ r♦s ♦r♥ ♥ ♥♦r♥ ♦♥t♠♥♥ts s♦ r♠♦ r♦♠ t sr ♦♥ t strtr s t♦ r♦♥ s s♦ ♦♥ s♣② s tt♥ t sstrt t♦ t sr s③ ♦ s t t♠tr t♦ r♣♦st ♦♥ t♦♣ sstrts r ♥t② ♥ ♥ssq♥t t♦♥ t♥ t♥♦ ts t st ♠♥ts ♦t ♥♥ ②trs♦♥ rt♦♥s

①t♥ st② ♦ sstrts s t♥ ②r ②st♠ s♦tt s s ♦r♠ ♦ ♥♥ s ♥♦t s♥t t♦ r♥t ♣rt sr trt ♥t ♥♥ ♥ ♥srt♦♥ ♥t♦ t ②r s②st♠ t sstrts r rst

Page 87: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❯ PP

r t♦♠ ♦r r♦s♦♣② t♦♣♦r♣ ♠♣s ♦ t r t♦♣ ♥♥♥tr ♥ t t♥ ♥♥ ♦tt♦♠ sstrt t♦♠ st♣s r s♦♥ t ttr t♦

♥st r+ t ♦r ♠♥ts r♥ ts ♣r♦r t s♠♣ s r♦tt ♥

Page 88: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P ❲ ❯ ❱P

♦rr t♦ ♥sr ♥♦r♠t② ♦ t t♥ s s ♦♦ ② ssq♥t ♣r ♥ ♥♥♥ ♥② rst♥ ♥ ♦♥t♠♥t♦♥r sr ♦ ts st♣s r r② st ♥ ♦♥r♠ ② t♦♠ ♦r r♦s♦♣② ♠sr♠♥ts s s♦♥ ♦♥ t ♥♥♥ ♦♥ s ♥♦t s♥tt♦ r♠♦ t sr ♦♥t♠♥t♦♥ ♥ t ♦tr ♥ t t♥ ♣r♦r♥rss ♦♥♥trt♦♥ ♦ ♣ t♦ ♥♠ ♣ ♦s t♥ t r②st t♦ r ♦t t t r ②r s sr ♥ st♦♥

♣ttr♥

♣ttr♥ s t♥ ♠ ❯❱ ♣♦st♦♥ ♠t♦ ♥ r♦♥ s rr♥ ♥ t♠r ♦♠s ♦♥③ ♥ r+ ♦♥s r rt t♦rs t trt s♦s ♦ ♣r ♠tr ♥♥t ♦♥s t t trt sr ♥ s ss ♦♦s♦♥s ♥s ①♥♥ ♠♦♠♥t♠ ♠♦♥ t ♣rts t ♥r② tt trt t♦♠ ♥s s rr t♥ ts ♥♥ ♥r② t ♥ t r♦♠ t trt♥ ♣r♦♣t t♦rs t ② ♣ s♠♣ ♦r ♥ ♣♦st ♦♥ t s♠♣♣♦♥ rr

♥tr♦♥s r s s t s♣ttr♥ ♦♥ s♦rs ♥s t s②st♠ ❬❪ ss ♦♥sst ♥ ♠♥t ♣ ♦ t trt ♥♦♠♥ r+ ♦♥s r tr♣♣♦♥ ♠♥t ♣ts ♥ t♦ ♠t♣t♦♥ ♦ s♣ttr♥ ♦s♦♥s t t trt ♠tr ♥ s ♦ ♠♥tr♦♥s ♦♥t♥♥ ♥ ♥st♥trt r♦rq♥② ♣♦r s♣♣s t♦ s ♥ ♦rr t♦ ♦ t r♠t♦♥ rt t t s t♥ t tr♦s s r s s t ts ♠♣♥♠t♥ ♥ t♦ qt② ♥st♥ ♠s ♥t ♦ t s♣ttr♥ s tt ♥ ♠trs t ♠t♥ ♣♦♥ts ♥ ♣♦st t ts ♣♦st♦♥ ♠t♦ ♦r♦r r ♥ t trt ♦♥t♥s♥ ♠♦♥t ♦ ♠tr s♥t ♦r ♦♥ ♣r♦ ♦ ♠♥t♥♥r st②

②r ②st♠ s♣ttr♥

st♦♠♠ s♣ttr♥ st♣ s t♥ t t♠r♠ ♦ ts tss s ♣♦ ♣♦st♦♥ ♦ r♦♥ ♦t ts ♦ s ♥ ♠♥s♠ ♠♦♥ ♠ts s s t ♥st♦r t♦ t ♠r s♥ ♦♥② tr s♣ttr♥ s♦rs♠② ♥st ♥ t ♠r t t s♠ t♠ ♠♣s tt ss t♦♠♣s♦r② ♥ trts ♦♥② ♦♥ ♦t ♦ ♦r ♦ ♦ s s ttr ♦♥ t♥ t s♠ rt♦♥ t s②st♠ s q♣♣ t t ❯❱s♠♣ tr ♥ t r+ t♥ ♥ ♦t ①t♥s② s ♦r t ♦r♠♥t♦♥♥st sstrt ♣r♣rt♦♥ ♦r t ♣♦st♦♥ s♣ttr♥ ♣♦st♦♥ rtsr rt s♥ t ♠ qrt③ ♥ ♠♦♥t♦r s②st♠ ss♦ q♣♣ t rs s ♥②③r ♦♥ t ♣rs ♦♥tr♦ ♦♣rt s ♣rssrs t♥ t ♠r s ♣rssr ♦ 2 · 10−9 ♠r s

Page 89: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P❯

② s♠t♥♦s s ♦ r♦tr② tr♦♠♦r ♥ tt♥♠ s♠t♦♥♣♠♣s

tr ♣♦st♦♥ s♣ ♣♦st♦♥ ♣rssr ♥tr♦♥ ♣♦r♥♠♠ 10−3 ♠r ❲

♣t♠③ ②r ②st♠ ♣♦st♦♥ s♣s ♥ ♦♥t♦♥s ♦r s♣♠trs

♥ ♥ sstrts ♥♠ t r ②r s ♣♦st s s ♥♦rr t♦ rtr ♥sr s♠♣ t♥ss ♥ r②st♥t② t s♦ t♦ tr♣ ♥② ♣♦ssr♦♥ ♠♣rts ♥r♥t ♦ t ♣♦st♦♥s ①♥ t ♦♥s rqr♥ s♦♠s s ①♣♥ ♥ st♦♥ ♦ ♣r♦r♠ t t s♠♣ rr♦tt♥ ♥ ♦rr t♦ ♥sr ♥♦r♠t② ♦ t ♣♦st ♠tr ts ♦ t♦♣t♠③ ♣♦st♦♥ ♦♥t♦♥s ♦r ♦ t s♣ttr ♠trs r ♣rs♥t ♥t

t♦♣ t r ②r t r♦♥ ♦tt♦♠ tr♦ ♠tr s ♣♦stts ♣r♦r♠ t t P s♦ tt t s ss♥t t♦ ♥♥ t ♦rtr♦ t ts ♣♦♥t ❬❪ tt s ♦r t rrr ♣♦st♦♥ ♥s♥ t ♦r ②r r♦t s ♦ ❱♦♠r❲r t②♣ s♥ ♦r♠t♦♥ ♥st ♦②r②②r r♦t ssq♥t ♣♦st♦♥ ♥ t♦ ♦♥t ♣♥♦s♥♥♥ ♦ t s♣♦st tr♦ ♦r r♦t ♥♦t ♦♥② r♠t②♠♣r♦s t qt② ♦ t ssq♥t② ♣♦st rrr t s♦ st♦ ttr ♣t①② ♥ ttr♥ ♠♥t ②strss ♦♦♣s ♦ t ♥tr s②st♠ st② r tt t s♥t ♥♥♥ ♦♥t♦♥ ♦r t r♦♥tr♦ s t

P♦str♦t ♥♥♥ ♦ t ♦r tr♦ t♦ ♥ ♥tr qt② ♣r♦♠ ♣rssr t♥ t ♠r rss r♥ t t♠♣rtr ♥♥♥ t♦ ♦tss♥ ♦ rt♥ ♠♥ts ♥ t ♥t② ♦ t tr rsts ♥ t♦♥t♠♥t♦♥ ♦ t ①♣♦s ♥tr ♦r t rt♦♥ ♦ t ♥♥♥ s rsts♥ st♦♥ ❯♥♦rt♥t② t♦ t ♠r s♥ t tt♥♠ ♠♥trt② s t s♠♣ ♣r♥t♥ t s ♦ ts ♣♠♣ ♥ ♣rs♥ ♦ t s♠♣s t♦ ♦ s♦ ♦ ♥♦r♣♦rt t♦♠s ♥t♦ t s♠♣ strtr ❲t♥ tt♠r♠ ♦ ts tss s♦t♦♥ ♥ t ♦r♠ ♦ ♥ ♦ ①t♥s♦♥ t♦ t♠r s ♣r♦♣♦s ♦ ♦ t tt♥♠ ♣♠♣ t♦ ♥ ♦♥st♥t st♦t t rs ♦ t♦♠s ♥ ♥♦r♣♦rt ♥t♦ t s♠♣ ♦r r♥t t♠ ♦ rt♥ t s♦t♦♥ s ♥♦t ♥ ② ♠♣♠♥t ②t

s ♣r♦s② ♠♥t♦♥ t r♦♥ ♦① ②r t t ♥tr♥ rs② t t s♣♥tr♦♥ rs♣♦♥s ♦ t s②st♠ ♦♥sq♥t② s♥

Page 90: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P ❲ ❯ ❱P

r ♦♥t t♦♠ ♦r r♦s♦♣② t♦♣♦r♣ t ♥ ♦ rr♥t rt ♠♣s ♦ ♥♦♥♥♥ t♦♣ ♥ ♥♥ ♦tt♦♠ r♦♥ ♦♥ t sstrt ♦t r♥s ♥ ss ♥ tt t ♦ rr♥t♦ts♣♦ts ♦rrs♣♦♥ t♦ t t♦♣♦r♣ s ♠sr♠♥ts r ♦♥t ♠❱ ❬❪

♣r ♥tr s ①tr♠② t t♦ r③ ①♣r♠♥t② t t t♦♠s ♥ ❲♥ t ♠♦♥strt tt ♥tr s ♠ ♠♦r ♦r t♥ t ❬❪ s♦ tt♠♣t t♦ ♥srt t ♥tr②r s t ♦①②♥ ♥trs♦♥ ♥t♦ t♦♣♠♦st ♠♦♥♦②rs ♦ t ♦rtr♦ ♦ s ts ♦①t♦♥ r♥ t rrr ♣♦st♦♥ t s t② ♦r tt t s t ♥tr tt ♦①③s ♠② ♥ rst ♥ t♦♥ ♠♦♥♦②rs rt♦♥ ♦r ts rs♦♥s ♠♦♥♦②rst ♥s♠②r s ♣♦st t♦♣ t ♦tt♦♠ tr♦

♥ t ♦tt♦♠ tr♦ s ♦♠♣t t rrr ♥ ♣♦sts s ♦♥ r♦♠ s♥ trt s♥ r♦rq♥② ♠♥tr♦♥ s♣♣t ♥ ♠♣♥♠t♥ ♦① t s ♥♦t tt t ♥t st ♣♦r

Page 91: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P❯

r ♦♥♦r♦♠t ①r② rt♦♠tr ❳ ♥ tr♥t♥ r♥t ♦r ♠♥t♦♠tr ♠sr♠♥ts ♦♥ t s② ①s ♦r♦ sts t ♥♦♥♥♥ s ♥ ♥♥ rs♦ ♦r tr♦ ♥st s♦s ♠♥♦r ♠♥t③t♦♥ ♦♦♣s ❬❪

♣♦st♦♥ ss sst♦♦♠tr② ♦ t trt t ♠ ♦①②♥♥t r♦♦r ♥ rs ♣♣r ♦♥ t s s♦r ♠♦r s r♦t rtsr sts ♣♦st♦♥ ♦ t rrr r ♠♥t ♦ t s②st♠s st ①t♥s② rs♣ttr♥ ♦ t rrr s ♣r♦r♠ t ♦rt♦t t ♣rs♥ ♦ ♦①②♥ ♥ t ♠r t ♥ ♠ t♦ ♦♥tr♦ t t②♣st♥ t rrr ❲ ♣rs♥t ts rsts ♥ st♦♥

♥ t rrr s ♣♦st t ♣♣r tr♦ ♥ r♦♥ t♦♣t rrr ♣♥♥ ♦♥ t s♠♣ st ts s tr r♦♥ r♦♥ t♥♦t ♦ ♦r ♦tr♦♥ ♦② ♦ s♣t t t tt t r②st♥strtr ♦ ♦t s ①♦♥ ♦s♣ ♣ ♦ ♥ ♠♥t♥ t strtr ♣ t♦ ♦tr♦♥ rt♦ ♦ t♥ t ♦② s t♦♦♠♣♦♥♠tr s ♥♦t s♣ttr r♦♠ s♥ trt t r♦♠ s♣rt ♥ ♦ ♦♠♥s♦rs s ♠♥t♦♥ ♦r ♦ ♥ trts ♥ ♥♦t ♠♦♥t ♥ t ♠rs♠t♥♦s② t♦ t ♠t s♣ ♦ t ♠r s rqrs t♦ ♣tr s♣r t t ♥tr ♦r t♦ r♦ r♦♥ ♦♥② ♣♣r tr♦ st ♦r♠r s rtr ♥♦r t ttr s s ♦s♥ ♦r ♥ ♦rrt♦ ♥sr rr♦♠♥t ♦♣♥ t♥ t tr♦s t② t♦ r♦♥t sst♥t② r♥t t♥sss

ss♥t strtr ♦ t ♠♥t t♥♥ ♥t♦♥ s t ts ♣♦♥t ♦♥♦r t r♦♥ s r② rt ♠♥t ♦ ♦①③ st ♦ st♥s t♦ ♦r t ♥♦♥♦①③♥ ♠t ♣♣♥ ②r ♦r s♦s♥ ♥ ♦rr t♦ ♦ s♦ t s♠♣s r tr♥srr t♦ t ♣♦rt♦♥ ♠r ♦t ②r ②st♠ t♦t r♥ t ♠ s s sr ♥ st♦♥

Page 92: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P ❲ ❯ ❱P

♥② ♣ttr♥

♠♣s ♥ t s♣r s s♥ t♥ t ♦ tr♦sr r♦♥ s t rst ♦ ♦♦rt♦♥ t ♥ r♦♠ t ♥sttt ♥♠♦r ♥ ♥② r♥ ♥② t ♥r r♦t ♣r♦r s ♣rs♥t ♥ t♠♥sr♣t ♦r ts ♣s rr t♦ ❬❪

s ♦s s②st♠s ♦ ♥♦t ♥ t♦ ♣♦st ♦♥ r②st♥ sstrt s t② r②st③ r♥ t ♣♦st♣♦st♦♥ ♥♥♥ ♣r♦ss s st♦♥ t r♦t s ♣r♦r♠ ♦♥ t ♠♦r♣♦s ♦r♥♥ ss ♥ ♦rrt♦ ssr ♥♦r♠t② ♦ t s♠♣s s♠♣s r rrs② tr♥st tr② r♥ t r♦t t♥t♠ ♥♠t ②r s s s t tt♥♥ ②r ♦♦ ② ♦♥♠ t♦ ♠♣r♦ rtr t①tr③t♦♥ t♦ ♦♦ s♦♥ ♦ ♦tt♦ t♥t♠ s s ♦♦ ② ♥ r♥♥♠ ♥trr♦♠♥t ♦s r♦ sr s♦rt② trrs t ♦♥♠♥♠♦♥♠♠♥ t♥♥♥ strtr s ♣♦st t ♠tr s♣ttr r♦♠ s♥trt ♦ ♣r♦♣♦rt♦♥s r ♦0.40.40.2 strtr s ♣♣ tt Pt ♣♣♥ ②r

s r② sr ♥ st♦♥ t ♦s s r ♥♥ ♣♦str♦t ♥ ♦rr t♦ ♦t♥ t t①tr r②st♥ rrr ♥ t ♥trrs ♦ t tr♦s ♦r t ♥♥♥ st♣ ♣②s ②t ♥♦tr r♦ st s②st♠ s ♦♣t♠③ ♦r ♣♦st♦♥ ♦ r♥ ♥trr♦♠♥t ♠tr rtrt♥ s②♥tt rr♠♥t sr ♥ st♦♥ ♣♥♥♥ ♦ t ♦r tr♦ s ② ♥♥♥ ♦ t s♠♣ ♦r t tt s ♦ t t♠♣rtr ♦ t r♥ ♥trr♦♠♥t ②t ♦ t r t♠♣rtr ♦t ♦ tr♦s t t ♦♥st♥t ♠♥t ♣♣ ♥ ♣♥ ♦t s♠♣ s ♥s t ♥♠♥t ♦ t r♥ ♥trr♦♠♥t ♥ ♦rr♦♠♥t ♦♠♥s ♣♦♥ t ssq♥t ♦♦♦♥ ♥ ts ①♥ s t♦r tr♦

s r♦t t♥q s rt♥ r ♥ ♦♠♣r t t ♦♥ ♣r♦♣♦s ② ❨s t ♥♠② t ♥ s♦♥ r♥ ♥♥♥ ♥♥t♥trr♦♠♥t s ts ♣♥♥♥ str♥t rs ts ♣♣r♥ t♥ t rrr ♥♥s t ♦r♥t tr♥s♣♦rt ♥ rs ♦ t ♠♥t♦rsst♥ t s ♠♦r ♣r♦♥♦♥ s t ♥♥♥ t♠♣rtr ♦r t♠♥rss ❬❪ ❲ sr ♥ t ♦r st② ♦♥ t ts ♥rt tt rr②st③ t♦ ts ♣♦st♥♥♥ ♣r♦ss ♥ st♦♥

♣rt r♦♠ ♠♥t t♥♥ ♥t♦♥ sts s♠♣s ♥ t t♦♣ tr♦r s♦ r♦♥ ♦r tr♦s ♦♦ ② ♦r ♥st♦r rrt ♦r ♦♣t sts ♦ t rrr r rs♣t ♦♥tr♣rts r s♦ssq♥t② ♥♥ ♥ ♦rr t♦ st② t ♥♥♥ ♠♣t ♦♥ ♦♣t ♣r♦♣rts♦ t rrr

Page 93: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❱P

♣♦rt♦♥

♣♦rt♦♥ s ♥ ❯❱ t♥ ♠ ♣♦st♦♥ ♠t♦ ♥ r t s♦s♦r ♠tr s t ♣ t♦ ts ♠t♥ ♦r s♠t♦♥ t♠♣rtr ②♦♥ ♣♦rt♦♥ ♥s t♦ t tr ♠ t♥ t ♠r t♠♥ r ♣t ♦ t ♣♦rt ♣rt s ♦♥ ♥♦ t♦ r t s♠♣ t♦t♦r t r② ♦s♦♥s r♥ ts t t♥ t ♦♥♥ss ♦♥ t sr

s ♠♥t♦♥ ♦r s♠♣ tr♥sr ♠♦♥ ♠rs ♦ ②r ②st♠♦rs t♦t r♥ t ♠ s t t♦♣♠♦st ♣♣r tr♦ ②rs ♦ ♦r ♦ r ♥♦t st t♦ ♦①t♦♥ s♠♣s r t♥ ♦r t ♥♠ t ♣♣♥ ②r ♦s ♣♦rt♦♥ s rr ♦t t t♦② ♠♥ ♣♦st♦♥ rt ♠t ♥tr ♦ ts ②r s rqr ♥♦rr t♦ ♣r♦ ♥ tr ♦♥tt tr t s♠♣ ♣r♦ss♥ s st♦♥ ♦rts

♥ ♦rr t♦ rtr ♥♥ t r②st♥ qt② ♦ t st ❬❪ t s♠♣s ♣♦st♥♥ ♦r ♦♥ ♦r t ♥ t ♣♣ s♠♣ s s② t♥♦t ♦ t tr ♠

Ps sr ♣♦st♦♥

r3 ♥ 2 s s♠♣s s s t ♦♥s ♦♥t♥♥ tr♦s r rt s♥ t Ps sr ♣♦st♦♥ P t♥q ② ♦s r♦♠ t ♣rt♠♥t ♠ t s tr① ♥♦r♥qs s rst ♦♥ ♥tr♥ ♦♦rt♦♥ t♥ t P

❲ t P r♦t s rt② s② t♦ r③ t ♠t♣st♣ ♣②ss♥r♥t s ♠ ♠♦r ♦♠♣①

sr ♠ s ♦s ♦♥ trt ♣ ♥r ♠ ♥ ♠ r♦♠ t♠tr t♦ ♣♦st ♣♥♥ ♦♥ t sr ♥t ♥ t ♦♣t ♣r♦♣rtsrt♦♥ ♥ s♦r♣t♦♥ ♦ t trt ♠tr t ♠ ♣♥trts ♥♠♥t♦ t trt t sr ♥r② s ♦ rt♥ trs♦ t ♥r②tr♥srr r♦♠ t sr t♦ ♠tr t t sr ♦ t trt s r ♥♦t♦ t ♣ t sr ♥ t ♣♦r③t♦♥ ♦rs t♦♠s ♦♥s strs t rtr♦r t r♦♠ t trt ♥ t ♠tr ①♣♥s s ♣s♠ ①♣♥s♦♥ ♣r♠trs ♦ t ♣s♠ r r♥ ② ♣♦st♦♥ ♦♥t♦♥s s♣②t ♣rs♥ ♦ ss ♥ ♦r♥ ♣rssr t♥ t ♠r s♣ ♥♦♥sq♥t② ♥r② ♣rts ♥ s♣ttr ♠tr r② ♣♦st ♦♥ ts♠♣ ♠② tr ts r♦t rt ♥ ♠♦r ♠♣♦rt♥t② st♦♦♠tr② ♥♦r♠t♦♥ strtr ts s♣② ♥ s ♦ ♦①s s♦♥ ♦♥ t r♦trt ② ♥ t ♠r t ♦①②♥ ♦ ♥sr ♥♦t ♦♥② ♥♦r♠t② ♦ ts♠♣ t s♦ ts ♦①②♥ st♦♦♠tr②

sr s ♦r t P ♣♦st♦♥ r♥ ts tss s r ①♠r srt t ♥t ♦ ♥♠ rq♥② ♥ t ♥r② ♥st② r ③ ♥

Page 94: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P ❲ ❯ ❱P

1.5J/cm2 rs♣t② s ♣rssr s ♦ 5·10−8 ♠r ♦r strtrsrt ts ② r②st♥ sstrts r s ♥ ♦rr t♦ s♦rsr ♦♥t♠♥♥ts t sstrts r ♥♥ ♦r ♠♥ts t s ♣rssr ♣r♦r t♦ ♣♦st♦♥ s ♦ 2 · 10−7 ♠r ♦r t♠♣rtr♣♦st♦♥ ♥ ♦ 9 · 10−8 ♠r ♦r t ♣♦st♦♥ t r♦♦♠t♠♣rtr rt② ♣rssrs ♠② rst r♦♠ t t tt t♦ ♦ s♣rt♦♥ ♠r t r♦t ♠r s rt② ①♣♦s t♦ t t♠♦s♣r r♥t s♠♣ ♦♥ tr t s ♥♦t ♦t

♥ ♦rr t♦ ♥ ♥ r②st♥ strtr t ♦r ♠♥t tr♦ s s② ♣♦st t t♠♣rtr s ♦r t rrr t s♣♦st t r♦♦♠ ♦r t t♠♣rtr s♣② t ♦tt♦♠ tr♦ s ♥♦① t♦♣ ♠♥t tr♦ s ♣♦st t ♦ t♠♣rtr ♥ ♦rr t♦♦ s♦♥ t t ♠♥t♥♦♥♠♥t ♥trs ♥♠ ♣♣♥ ②rs r♦♥ t♦♣ t strtr ♥ ♦rr t♦ ♣rsr t r♦♠ ♥② rtr ♦①t♦♥

t♦♥ ♥r② tr♦♥ rt♦♥

P ♠r s q♣♣ t rt♦♥ ♥r② tr♦♥ rt♦♥ s②st♠ tt ♦s t♦ ♠♦♥t♦r ♥st t s♠♣ qt② ♥ ts r♦t♦♥tr♦ t♥q ♥ tr♦♥ ♥ ♥rts ♥ tr♦♥ ♠ tt ♠♣♥s ♣♦♥t s♠♣ sr t ♦♥② rs ♥ ♥ rt t tr♦♥s rt tt♦r t tr s♣ rt♦♥ ♥s r t② ♥trr ♦♥strt② ♦rstrt② ♥ rs t♦ s♣ rt♦♥ ♣ttr♥ t t tt♦r sr♥ tts rt② rt t♦ t r♣r♦ tt ♦ t ♠tr ♥②ss ♦ t ♣ttr♥ ②s ♥♦r♠t♦♥ ♦t t r♦♥ss st♦♦♠tr② ♥ r②st♥t② tt rr♥t st ♦ t r♦t sr♣♥ss ♦ ♣s ♥rss t t srr②st♥ qt②

Page 95: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♣tr

r♦♠ s♠♣s t♦ s

r♥t t♥qs ♦ s♠♣ r♦t r ♣rs♥t ♥ t st ♣tr ♥♦♠♣t ts s♠♣s r ♣r♦ss ♥t♦ ♦r♥ s s ♣tr ♣rs♥tst♦ r♥t ②s ♦ ♣ttr♥ rst ♠t♦ t ♥st t②♣ s ①s② ♦r ②r ②st♠ s♣ttr s ♥ rs ♦♥ s♣ttr♣♦st♦♥ tr♦ s♦♠ss s t♥q ♦s ♥♦t rqr t s♠♣ t♦♥r♦ ♦♥ ♥ t ♣♦t♦t♦r♣② s ♣rs♥t ♥ t s♦♥ st♦♥ ttr ♠t♦ t t ♦st ♦ ts ♦♠♣①t② ②s ①♥t s♣t rs♦t♦♥ ♦s ♥t♦♥s rt ts ② t♦ ♦ ♠ s♠r s③s ♦r♦r trsts ♥ r ♥♠r ♦ s ♣r s♠♣

♥st ♣ttr♥

❲t♥ t t♠r♠ ♦ ts tss t ♥st ♣ttr♥♥ t♥q s sts♦r t ②r ②st♠ s♣ttr♥ ♣♦st♦♥ s ♥ ♠♦♥t♥ ♦ ♥ t♦♥ r♠ ♥s t ❯❱ s②st♠ t s♦♠s s②st♠ tt t♦ t s♦♠s r♠ ♥ ♣rs② ♠♦ ♦♥ tr ♠♥s♦♥s ♦♠♥ ♥ ♥♦t ♦ t ♦♥tt ♣♦st♦♥ s ♠s t ♣♦ss t♦ ♣♦st ♦♥st ♠trst sr ♣ttr♥s t♦♣ ♦tr

♥st ♣ttr♥♥ ♣r♠trs ♦ ♣♦st♦♥ r ss♥t② s♠ s ♦r tst♥r ②r ♣♦st♦♥ ①♣t tt t ♣♦st♦♥ ♦rs t s♠♣s ♥ ♦♥tt t t s♦♠s ♣r♥ts t s♠♣ r♦tt♦♥ t♦ ts②st♠ ♦♥strt♦♥ s s t♦ r ♦ s♦ ♣♦st♦♥ ♦♥ t s♦ t ♠♦t ♦r♦r s ♥ s♥ r♦♠ t s♠t r t t ♥♦ss t♥ ♥♠ ♦r tr♦ s ♥♥♦t ♥ ♣r♥♣ ♦r ♣r♦♣r② tt t♥ rrr ♠tr ♥r ♠♦r t♥ ♥♠ ♥ ♦rr t♦ ♦ s♦rtrtst♥ t♦♣ ♥ ♦tt♦♠ tr♦s ♦♥ ts s ♦ t ♦tt♦♠ tr♦ ♥t♦♥ st♣ s ♥tr♦ ♣ttr♥ ♥♠t t♥♦♦ s♣♦st st tr t rrr r♦t st♣ ♥ ♦♥② ♥ ♦♣♥♥ ♥ t ♠♦ t ♦tt♦♠ tr♦ tr♦ t t♦♣ tr♦ ♠tr ♦ ♦♥tt t

Page 96: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P ❱

r ♠t strt♦♥ ♦ t rr♥t t t tr♦ s t ♥ts ♣r♥t♦♥ ② ♥tr♦t♦♥ ♦ t t t♥♦♦ rt ♦♦rs ♣tt ♥st♥ sstrt t ♦♥t♥ tr♦s ♥ ♦t rrr ♥t♥♦♦ r② ♥s s♦ t rr♥t ♦ ♥♥s ♦r ♦t ss♦t tt t ♣tr s ♥♦t t♦ s

r ♠t strt♦♥ ♦ t ♥st ♣ttr♥♥ r♥ t ♣♦st♦♥t ♦r tr♦ ♣♦st♦♥ ♥tr t♥ rrr r♦t tr♥s♣r♥t ♦♦ ② t t♥♦♦ t ♥tr♦t♦♥ ♥ ♦rr t♦ ♦r t ♦r tr♦ s rt t♦♣ ♦♥tts rt♦♥ ♥ t t♦♥ t♥ ♣♣♥tr♥s♣r♥t r sqrs ♠r t ♥t♦♥s ♣♦st♦♥

rrr rt② ♦♥ t rrr t♥♦♦ st♣ t② ♥ t♥t♦♥ ♥t ♥ ♦♥ t t t ♦ t ♦tt♦♠ tr♦ ♦♥sq♥t② t r

♥ t ♣♦rt♦♥ ♠r ♣rs♥t② s s♦♠s s②st♠ ♣♦st♦♥ ♥ tt ♠r s ♥♦t s ♥st t s♠♣s r ♦r tt ♥st♥ ♥♠ t ♥ t ♦tr ♥ t ♥st♥ ♥tr ♦ t ♣♣♥ ②r ♥♦t ♣r♥t ss♥ t ♦♥t ♠tr ♦ rs♦♥ s tt t s♦♠s ♣ttr♥ s♠♣ ♥♦t t♦ ♣r♦ss ②t ♦♣t t♦r♣② t rt② ♥r♥t t ♦♥t♣ ♦♥♥ ♦♥♥ s r♥ ts tss s② ②♣sss t ♥♠ t♥ ♥st♥ t♦♣t ♦♥tts s st♦♥

t♦ t ♠t s t♥ss ♦ t ♦tt♦♠ tr♦ t♥♦♦ ss ts t s st t♦ 650µ♠ r ♥♦ t♦ ♥sr ♦ rsstt② Ω ♥♦t t t ♣r♦♣rts s tr t r s ♥② 50µ♠ ♦r 100µ♠ ♣♥♥ ♦♥ t ♠s ♣ttr♥ ♦♣♥♥ ♥ t t♥♦♦ ♥ t t 50µ♠ t ♦ t t♦♣ ♦♥tts t♦ t ① ♦ tt♦♣ ♦♥tts t tr ♦ rsst♥ Ω s ② ①t② ♦t♥ss ♠♥tt♦♥

Page 97: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P❨

r Ptr ♦ s♠♣ ♣ttr♥ ♥st s♥ t s♦♠s t♥q ♦♣♥♥ ♥ t t♥♦♦ ♥♥ t r 2500µm2 ♣r ss ♥ ♦r♠ ♦ t rt str♣ ♥ t ♠ ♦ t ♦tt♦♠ tr♦ tt ♥trsts ♦ t t♦♣ tr♦s

rs ♦ s rt t t s♦♠s r 2500µm2 ♦r 5000µm2 ♠ rr t♥ ♦ ts ♦t♥ t t ♦♣t t♦r♣② sr ♥ t ♥①t♣tr ♦r t ♥st ♣ttr♥♥ s♠s ♣r♦♠s♥ s t ♥t♦♥s ♥ rt t♥ rt② s♦rt t♠ s ♦♠♣r t♦ ♦♥ ♥ t ♠tst♣t♦r♣② ♣r♦ss t②♣ s♠♣ rt s♥ t s♦♠s ♣ttr♥s ♣rs♥t ♥ r

♣t t♦r♣②

♣t t♦r♣② ♦s ♠r♦♠trs ♥t♦♥ ♦ ♣ttr♥s ♦♥ t s♠♣t s ② s ♦r rt♦♥ s ♦ t r qt② ♥ s♥♦ tr♦t t sr ♦r t t♦r♣② ♣r♦ss ts st♣s r rr ♦t ♥ t ♣ t t♥♦ ♥r♦♦♠ r ♠♦st ♦ t q♣♠♥t ss♥t♦r t ♣r♦ss s ♥st

Page 98: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P ❱

t♦r♣② ♠s

r ♥ s♦tr ♠s rs r♥ ♥ r tr♥s♣r♥tt t ♦♥s ♠r t ♦♣q rr♦s ♠r ♠♦ts s r♥ ♦rrs♣♦♥♥t♦r♣② st♣s r sqrs ♠r d r t♦r♥ sqrs

♥ ♦rr t♦ st② ♥st t rsst ♥ ♦♥st② ♦t♥ sr ♣ttr♥s ♦♥ t s♠♣ t♦r♣② ♠s ♦♣ ② ♥♥ r♦♠ t ❯P②s r♦♣ s rs♥ s♥ t ♥ s♦tr ♣tt♦♥sr ♣r♣♦ss ♦ t ①♣r♠♥t ♥ ♥ t♦r♥ st♣ s♦ s t♦ ♠♣r♦rs♦t♦♥s ♦r s♠ ♣ttr♥s ♦♥ t②♣② s♠ ①♠♠ s♠♣s t♦st♣ strt② ♦ rr♥t ♥t♦♥ ♥t♦ t ♦tt♦♠ tr♦ ♦tr ♦♥t♥ ♦♥♥t♦rs ♥

Page 99: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P❨

r ♥ s♦tr ♥r s③t♦♥ ♦ t s♠♣ t ♦r ②rs♦r♣♣ ♦r t rr t♦

rs ♦♥ ♣♦ss ♦♥♥t♦♥s ♠♦♥ t tr♦s t♦♥ ♠♦ts s♦ st♦ ♥rs t rs♦t♦♥ ♦ t ♥♠♥t t♥ t♦r♣② st♣s ♥ srstrts t♦ ♦♥r ♦♣t ss t♦ ts s ❲t ts ♥s ♣r♦r♠t t ♦♥st ♦ t tss ♠♥♦r ♠♣r♦♠♥ts r ♣r♦r♠ r♥ t tss s♦s t♦ ♦♣t♠③ ♥t♦♥ s③s tst ♠s rs♦♥ t t t♠ ♦ rt♥ t♠♥sr♣t s s♦♥ ♦♥ r ♣r♣♦st♦♥ ♦ t ②rs s ♣t ♦♥ rs s ♠♥t♦♥ ♦ t ttr s♦♥ s♦♠ ♦ t ♦r♠♥t♦♥ trs ♠s ♥s t ♣ttr♥♥ ♦ st ♥t♦ r♦s ♦♥t♥♥ ♥t♦♥s ♦ t s♠ s③ ♥t♦♥ s③s r ♥

Page 100: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P ❱

r ❩♦♦♠ ♠ ② ♥ s♦tr ♦ t s♠♣ t ♦r ②rs♦r♣♣ ♦♦rs ♥ t ♦♥st ♣♦t♦t♦r♣② st♣s ② sr ♥t ♦♦♥ st♦♥ r♦♥ ②♦ ❱r♥ A ♥ rr t♦ tr♦ ♥♠r ♥ t ♠tr ♦ ♥t♦♥s ♥ t r♦ ♥ µ♠ rs♣t② r♦sss♥ ♣rs ♥ t ♦tt♦♠ ♣rt r ss♥t ♦r ♣rs ♥♠♥t ♦ st♣s rs♣② ♦r t ♠t♥ ♥♦t ss t♥ ♥♠ ♠r♥ rr♦r

µ♠ ♥ ♠tr rs♣t② t♦ rs♦t♦♥ ♣r♦♠s ♦♥r♥♥ t s♠st♥t♦♥s ♠♦t♦♥ ♦ s③s s ♣r♦♣♦s t t t♠ ♦ rt♥ s③s ♦♥t♦♥s ♣ t tr♦s ♥ ♦r ♣rt ♦ t ♠s r t s♠ s ♦ ts♥ t ♣♣r ♦♥ s ♠①♠♠ ♥♠r ♦ ♥t♦♥s rt r♦♠ ♦♥ s♠♣t♥ s♥ t♦r♣② ♣r♦ss s

♠s t t♦r♣② ♠♦ts ♣r♥t ♦♥ ts r♦♠♠ s tt ♦♠ ♥t♦♦♥tt t t s♠♣ r♥ t ❯❱ ♥st♦♥ s♠♣ ♠♣r♥t ♦♥sst ♦♠♥ts r♦♣ ♦♥ ts qrtrs qrtr ♦♥t♥♥ ♣ttr♥s ♦r t rs♣tt♦r♣② st♣ ♦ t ♠♦ts r ♠t♣ ♠♣r♥t♦♥ s♦♠♦ t♠ s♦ tr trt♦♥s ♥ rrs ♦ tr♥s♣r♥② ♦r ♣r♦ss♥♦ ♣♦t♥t ♦r♥ s st♣s ♥ ♥ ♠t♥t♦♥ ss ♣ttr♥st♣ ❱ ♦r tr ♦♣t sts t♥ t t♠r♠ ♦ ts tss s ♦♥②♦r tst♥ ♣r♣♦ss t s ♦ t ♠s ♣ttr♥s ♥ t ♣r♦ss

Page 101: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P❨

♣rs♥t ♥ t ♦♦♥ sst♦♥s

P♦t♦rssts

P♦t♦rssts P r ts♥st ♠trs ♠♦st② ♣♦②♠rs t ♦♥ str♥t♦ ♥s ♥ ①♣♦s t♦ tr♦t t s trs tr s♦t②♥ s♣ ♦♣rs s tr s ♥♦ ❯❱ ♠♥t t ♣rs♥t ♥ t t♥♦♥r♦♦♠ ♣♦t♦rssts ♦ ♥ tr ♣r♦♣rts ♦♥② ♥ ①♣♦s ♦♥ ♣r♣♦s♦ ♥r t②♣s ♦ ♣♦t♦rssts ♥ st♥s ♣♦st ♦♠♠ ♠♦r s♦ ♥ ♦♣r tr t ❯❱ ♥st♦♥ ♥ ♥t ♦♠s♦② ♦♣ tr ♥ ①♣♦s t♦ t tr♦t t rsts r♦♠str♥t♥♥ ♦ t ♦♥s ♥♠ ❯❱ ♠♣ s r♥ ts tss ②15mW/cm2 t ♦s

r ♠t r♦ssst♦♥ ♦ ♣♦st t ♥ ♥t rt♣♦t♦rssts tr tr ❯❱ ♥st♦♥ ♥ ♦♣♠♥t ♦t t ♦r♥ ♦ t♥t P

r ♥st ② t ❯❱ t s ♥ ② ♦r♥ ♣rts ♦ t ♣♦t♦rsst♦r s♠♣ t t t♦r♣② ♠s ♣♥♥ ♦♥ tr ♣♦t♦rsst s♣♦st ♦r ♥t ts s qr st♥t s♣ ♣♦♥ ♦♣♠♥t s♣② t s ♦ t ♥t rsst s r ♥ ♦rr t♦ ♦t♥ ♥ ♦r♥ tt ❲t♥ t t♠r♠ ♦ ts tss t♦ s♣ ♣♦t♦rssts r st ♣♦st ♥ t ♥t ❩

P♦st ♣♦t♦rsst

Pr♠trs ♥ ♦r ♦rrt rsst rs♦t♦♥ r st ♥st♦♥t t ❯❱ t ♦r s♦♥s ts ♦♣♠♥t ♦r s♦♥s ♥ ♦♣r ♥ rtr ♦t ♦r s♦♥s t ♥ ♦rr t♦ ♠♣r♦ tsstt②

t ♣♦t♦rsst ❩

♥ ♦rr t♦ ♦t♥ t sr ♦r♥ t t ♣♦t♦rsst tt s r ♦rt t♦ ♣r♦ss sr ♥ sst♦♥ t ♥t P ❩ ss s ♥t② ♣♦st ♣♦t♦rsst ♠② ts ♣♦rt② ♥rt ② ♦t♦ ts ♥st ♣rts ts ♣r♦ss♥ ♣r♠trs r st ♥st♦♥ tt ❯❱ t ♦r s♦♥s t♥ t ♥ ♦rr t♦ ♥rt ts ♣♦rt②

Page 102: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P ❱

♦♦ ①♣♦sr t♦ t ❯❱ t ♦r s rtr st str♥t♥♥ ♥ ♥s♦♥ ♦♣♠♥t ♥ t ❩ ♦♣r

Pr♦ss♥

♣♦t♦t♦r♣② ♣r♦ss ♦♥sst ♦ ♦r st♣s sr t♦ ssq♥t②♣ttr♥ t s♠♣ ♥t♦ ♠♦r ♦♠♣① strtr ♦ ♥② ♦r♠ t s r ssq♥t② ♥t♦♥ ♣r ♥t♦♥ ♦r tr♦ ♣ttr♥ ♣sst♦♥ ②r ♣♦st♦♥ ♥ ♥ ♠t③t♦♥ ❱ ❲t♥ t t♠r♠♦ ts tss ♥ t♦♥ t♦r♥ sst♣ s ♥tr♦ ♦ t♦r♠♦ t ♥♥t t ♣♦t♦rsst r♦♠ t s ♥ ♠♦r ♣rs ♥t♦♥♦ ♠♦ts t♦r♥ sst♣ s ♦♣t♠③ t♦ ♣r♦r♠ ♦r ♦t ♠♥ st♣s t♦ t♦ rst♥ ss s st♦♥ t s s♦♥② rqr

P♦t♦rsst ♣♦st♦♥ ♥ ts t♦r♥

P♦t♦rsst ♣♦st ♦♥ t s♠♣ ♥ r♦♣ts t♥ s♣♥♦t ♦r s♦♥s tr♣♠ ♦r ts sr ② s♣♥♥♥ t s♠♣ ② t ♥ ♥♦r♠②r ♦r s♣t ♥ ♦rrt② t ♦r t ♥tr s♠♣ sr t♣♣r t♦ ♠ tr t t s♠♣ s ♥ ♦rr t♦ rtr ♠♣r♦ ts♥♦r♠t② ♥ t ♥tr ♦ t s♠♣ t s ♦r ♠♥ts t

♦r ♦t ♣♦t♦rsst t②♣s t ♠♦♥t ♦ sst♥ ♥ t s♠♣ s st♦♦ t♦ ♣r♦ rtr ♦rrt ♦♥tt ♦ t ♥tr ♣rt ♦ t s♠♣ tt ♠s r ♦r t qt② rs♦t♦♥ ♦ ♠♦ts ♥ ♦rr t♦ ♦ ts♣r♦♠ t t♦r♥ sst♣ s ♦♣t♠③ s♦ t ♦ ♣r♦r♠ t t♥♥♥ ♦ t♦r♣② st♣ ♦♥ t ♦tr t P ♦r ♦t P t②♣s tss ♦♥ ② s ❯❱ ♥st♦♥ ♦ t ♦tr rsst ♥ t ♥tr♥ s♠♣r ♦r t t r sqr ♠♣r♥t ♦♥ t ♠s str♦♥② ♥strsst s t♥ ♦♣ ♦r s ♦r s ❩ ♥ ♦♥② t rsst♥ t s♠♣ ♥tr ♥ t r t♦♥ s t♥ t s♥ ♦r t rsst ♥ ♦rr t♦ ♣♦rt t ♦♣r ♣rts r♦♠ t t♥ s ♥♦t ♣r♦r♠ ♦♥ t ❩ rsst s ♦ ♦ s♦ ♦ ♣rt②♥rt ts ♣♦rt② ♥ t r② st

P Pr ♥t♦♥

❲ ♥ ♦♥② t t ♥ ♥♦r♠ rsst t ♦♥ t s♠♣ ♣rs♦♥tt ♦ sts t♥ t s♠♣ ♥ t t♦r♣② ♠s

♥t♦♥ ♣r ♣ttr♥ s s ♥ ♦rr t♦ ♥ t t ♥t♦♥r r ♦♥tt ♣s r ♥ ♥ ts st♣ s ② ♦ ♦t rr♥t ♦ t♦rs t ♦r tr♦ ♦ ♥ ♥ t st♣

Page 103: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P❨

r ♠t t♦♣ ♥ r♦ssst♦♥ ♦ t ♣♦t♦rsst st♣ ♣ttr♥♥♦♦rs ♣t rs♣t② tr♦s r② rrr ②♦ ♠t ♣♣♥②r r ♣♦t♦rsst t s♦♠s ♦♣q r t♦r ♣♦t♦rsst ♥♦♥tt t t ♠s st ♦r ts ♥st♦♥ st ❯❱ ♥st♦♥ ♣r♦ss ♣ttr♥ ♣♦t♦rsst r♠♥♥ ♦♥ t s♠♣ sr ♦t t ♣tr s ♥♦t t♦t s

♣♦t♦rsst s st② ♥st ♥ r♠♦ ② ts ♦♣♠♥t r♦♠ t rs ①♣t ♣rs ♥ ♣s

r t♣ t♥ s♠ ♥ st r+ t♥ ♦♥ t♦ trrr s♠♣ s♠t tr t ♣♦t♦rsst r♠♦

r+ t♥ ♥ ♦rr t♦ r♠♦ ♠tr r♦♠ ♥♦♥♦r ♣rts ♦ t s♠♣t s♠♣ ♥r♥t t r+ t♥ ♣r♦r ♥ ts ❯❱ t♥q ♥trr t♦♠s r ♥t ♥t♦ t ♠r ♥ str♣♣ ♦ tr tr♦♥s t♦ rt ♣s♠ ♥ r+ ♦♥s r rt t♦rs t s♠♣ s♥ ♦s♦♥s ♥r♠♦♥ t ♠tr ♥ ♠② s tt ts ♣r♥♣ s s♠r t♦ t s♣ttr♥♣♦st♦♥ ♠t♦ t t r r♥ tt tr s ♥♦ trt r♦♠ t ♠tr s s♣ttr t s t s♠♣ r♦♠ t ♠tr s r♠♦ ♦♣r♦tt t t♥♥ rrr r♦♠ ♠ rt♦♥ ♦ ♦♥t ♠♥ts t♥

Page 104: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P ❱

t rrr t r+ ① ①t♥ t ♥ s ♥tr③ t♥s t♦ t tr♦♥♠tt♥ ♠♥t r t♦♥ s ② tt♥ ♦♥t t♣t♦ t s♠♣ ♦r♥rs ♦r ② ♦r♥ t♠ t s♠ ♠♦♥t ♦ t sr ♦♥t♣st ♥ ♦rr t♦ ♥sr t♥ ♥♦r♠t② t s♠♣ s r♦tt r♥ t♣r♦r

t♥ ♣r♦r s rr ♦t ♥ s♠ st♣s ♥ t r ♣♦♥t♦ t ♥t♦♥ ♣r t♥ s t♦ st♦♣ t♥ t rrr ♦r st t ts ♦r ♥tr t♥ ②♦♥ t rrr ♥ s t ♦r tr♦ ♠tr t♦ ♦rt ts t② ts t♥ss ♦ r s ♥ t ♦ttr ♦♥tt② ♥ ts ♠♥t ♦r ♦ t tr♦ ♦r♦rt t ♦♥t ♠tr ♥ r♣♦st ♦♥ t rrr s s♥ tss♦rtrt ♥♦tr ♣r♦♠ rs♥ r♦♠ t tr♦ ♦rt♥ s♣②♦r 0.7r0.3♥3 s trt♦♥ ♦ ts st♦♦♠tr② t s ♥♦♥ tt ♦①②♥♥t ♠tr ♦♠s s♠♦♥t♥ ♦r ♥ ♥st♥ ❬❪ s s② ♥♦r s t ♦st ♣♦ss ♦♥tt rsst♥s r ♥ ♥ ♦rr t♦♣r♦r♠ ♦rrt ♠sr♠♥ts ❬❪ s st♦♥

r tr♦♥ s♣tr♦s♦♣② ♥ ♦rr t♦ ♦rrt② tr♠♥ t t♥ ♣tt t♥ ♠r s q♣♣ t r tr♦♥ s♣tr♦s♦♣② s ♦r♠ ♦s♣tr♦s♦♣② s s ♦♥ t r t ♥ t t♦♠ ♣r♦ ② t tr♦♥♠ ♠② ts ♦r stt tr♦♥ r♠♦ ②♥ ♥ ♥st ♦ s stt♠② ② ♥ tr♦♥ r♦♠ ♥ ♦tr s ♥ ts tr♥st♦♥ ♥r② ♠② tr♥srr t♦ ♥♦tr ♦tr s tr♦♥ t ♥r② ♦t♥ s s♥tt♦ ♦r♦♠ ts ♦rt ♥♥ ♠② ♠tt r♦♠ t t♦♠ t rt♥ ♥t♥r②

r tr♦♥ ♣tr♦s♦♣② t t t♥ ♠r s q♣♣t③s ❱ ♥♦♠♥ tr♦♥ ♠ r tr♦♥s ♠tt r♦♠ rst ♠♦♥♦②rs ♦ t sr r st ♥ tr ♥t ♥rs ♣ t♦ ❱ ❬❪ s②st♠ ♦ t♦ ♦♥tr♦ t t♥ ♣t ♣rs② t ♥♦t rt② r♥t t♥ ♣r♦ss ♦r t♥ rs♦♥s t r ♥ ♥ tt♦r r ♠♦♥t♥ r♥t ♣♦st♦♥ t♥ t t♥ ♥ ♥ ♦rr t♦ ♣r♦r♠ t ♠sr♠♥tt s♠♣ s tr♥srr t♦ t r ♣♦st♦♥ t♦t r♥ t ♠ ss t♦ tr♥ s♠♦s t♥ st♣s ♦ s ♦♦ ② t r♠sr♠♥t ♥ ①♠♣ ♦ t t♥ sq♥ ♦r t ♦ s②st♠s s♦♥ ♦♥ tr t rst t♥ st♣ t rst ②rs ♦ tsr r ♣r② ♦t t♦♠s s♦♥ ♦♥ r ②s ♣s r♦♠ ♦t r♦♥♥ ♦t s♦ t ♦ ♥tr s ♥♦ ①♣♦s tr t♥ st♣ ♥s t♥ t t♦♣ r♦♥ ②r rs tr t ♦rt st♣ r♥ t rrr strt t♦ s t s♠ q♥tt② ♦ ♦ s♥ ♣s r♥♦t s t♥ ts ♥r② s♣♥ ♥ ♦rr t♦ tr♠♥ tr t r♦♥ ♣s

①♣r♥ s♦s tt sr s♠ t♥ ♦ss ♦t② t♦ ss t♥ t♥ ♥rt s♥st♣ t♥ ♦s

Page 105: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P❨

r r s♣tr♦s♦♣② ♠sr♠♥ts rts tr ssq♥t t♥s♦ t ♦ st ♦♥st rsts r st ♣rs ♦r rt②rs♦♥s rr♦ s♦s t t♥ ♦rr r♦♠ rst t♦ st ♣ ♣♦st♦♥s rr♦♠ rst t♦ s♠st ♣r ♠♥t ♦♥♠ ♥♠♥♠ ♣s r ♥♦t s

♦♠ r♦♠ t ♦tt♦♠ ♦r t♦♣ tr♦ t s♠♣ s trt ♥ t s♠ t♥ ♦s ♣♥ s♦ ♥ s♥ ♦ t ♣s s ♠♥stt t ♦r♠r t♥ st♣ ♥t r♠♥♥ts ♦ t ♣♣r tr♦ ♥tt t s t tt s ♥♦ t s♠♣ sr ②r s sr ♦t ttt t♥ ♣r♦r ♦s ♥♦t t t s♠♣ r♦♥s r ♦r ② t♣♦t♦rsst ♥ t r ♠ s ♦s ♦♥ t t ♦ ② ♦♥② tr r♦♥ ♣ st② s ♥②② t ❱

P ♦r tr♦ ♥t♦♥

tr t ♣r t♥ t st♣ ♣♦t♦rsst s r♠♦ ♥ s t♦♥ ♥t♥♦ trs♦♥ ts t ts ♣♦♥t t ♦tt♦♠ tr♦ ♣ttr♥♥ st♣ s♣r♦r♠ s♥ t ♣♦t♦rsst s st♣ s ①♣r♠♥t② r③ ts♠ ② s t rst ♦♥ ①♣t tt t s♠♣ sr s ♦r t ts♦♥ st♣ ♦tt♦♠ tr♦ ♣♦t♦rsst ♣ttr♥ t s tr t t ts♠ r+ ♠ ♦♥ t♦ t sstrt s ♦r t rst t♥ st♣ s♦t ts ♣♦♥t t ♦rt s ♥♦t sr s s s♣② t s ♦r r3

sstrts ♦s ♦♥t♦♥ ♥ ②s ♦s t t r♠ ♥ ts♥② ♦①②♥ sst♦♦♠tr② ♠② s t sstrt t♦ ♦♥t s s ②

Page 106: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P ❱

r ♠t ♣tr ♦ t s♠♣ tr t st♣ t♥ ♥ t ♣♦t♦rsst r♠♦ t r♦♥ ♦♦r ♥ t t♦♣ r♣rs♥ts t ♥st♥sstrt

♥♦r s s♥♥t ♠♦♥t ♦ rr♥t ♦ ♦ tr♦ t sstrt ♥t♦♥ t♦ t ♥♦r♠ ♥t♦♥ rr♥t ♥rss t rs ♦ s♦rtrtt♥ t♦♣ ♥ ♦tt♦♠ tr♦s ♦ ♥ ♥t♦♥

P Psst♦♥ ②r ♣♦st♦♥

♥ ♦t t ♥t♦♥ ♣r ♥ t ♦tt♦♠ tr♦ r ♥ 2 ♣sst♦♥ ②r ♣♦st♦♥ s ♣r♦r♠ ♥ ♦rr t♦ ♦ s♦ t ❩ ♥♠t ♥t ♣♦t♦rsst s ♣♦st t♦♣ t rs r t 2 ♣rs♥s ♥♦t sr s r s♣② s♠ rs t♦♣ ♥t♦♥ ♣rs ♦ t♦ rt ♦♣♥♥s t♥ t 2 ②r ♥ ♦rr t♦ ♣r♦ rtr ♠t♦♥tt ♥ t ♦♦♥ st♣ ❱ s t ♣♦t♦rsst s ♥ ts st♣ s ♥tt ♦r♥ ♦♥ ts s r♠♥ tr t ♣ttr♥♥ trrs t ♥♠t 2 ♥st♦♥ ②r s r♦rq♥② s♣ttr ♦♥ t s♠♣ s♥ t♦rr ♥tr♥t♦♥ ♥ s♣ttr♥ st♣ t ♦ r♦♣♥♥ ♠ ♣♦②♠rst ♠tr① P ♦ts t t♥♦ ♥r♦♦♠ s s ♦♥ ♥ ♦♦rt♦♥ t ♦s r♦♠ t r♦♣ ②r s ♣♦st r♦♠ s♥ 2 ♥ ♠tr trt ♣ ♣r ♥ ♠ ② r♦♠ t s♠♣ trt s ♣rs♣ttr ♦r ♠♥ts ♦r ♣♦st♦♥ ♥ ♦rr t♦ r♠♦♥② ♦♥t♠♥♥ts s♠♣ s r♦tt r♥ t r♦t ♥ ♦rr t♦ ♥sr ♥♥♥ ♥♦r♠t② ♦ t ②r ♣rssr ♣r♦r t♦ t ♣♦st♦♥ s t♥t 10−6 ♠r r♥ r♥ t r♦t t s r♥ 1.1 · 10−3 ♠r ♥r♦♥ ① ♦ s♠ ♣♦st♦♥ s♣ ♦ s ♥ t t♥ss r♠sr ♥ t rt♠ t qrt③ r②st ♠r♦♥ r♥ t s♣ttr♥♣r♦ss t s♠♣ t♠♣rtr ♥rs ♣ t♦

t♦ t♦ t 2 ♠t s♦♥ t♦ s♦♠ ♠trs trs♦♥s ♦ ♥♦t♥ ♥r s t♦ r♠♦ t ♣♦t♦rsst ♥ t 2 r♦♠ t♦♣ t ♥t♦♥

Page 107: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P❨

r ♠t ♣rs♥tt♦♥ ♦ t t♦r♣② st♣ ♥t ♣♦t♦rsst tr ts st ♦♣♠♥t t 2 s♣ttr♥ ♣♦st♦♥ s♠t ♦ t s♠♣ tr t t♦ ♣r♦ss ♥♦r♠② s♠tr♥s♣r♥t 2 ♦♦rs ♦♥ r tr ♥ t t♦♣ ♥ ♦rr t♦ s♦ tttr r r♥t ♠trs ♥r♥t

♣rs ♥st t s♠♣ s t ♥ t t♦♥ t ♦r t st ♦rs t♦ t ♣rs♥ ♦ t rsst ♦r♥ t t♦♥ tts t ①♣♦s ss ♦t rsst ②r tt ♥♦t ♥ ♦r ② 2♥ ss♦s t ss♦♣♦t♦rsst s t♦ r♦♠ t s♠♣ sr ♦♥ t t 2 t♦♣ tsrt♥ ♦♣♥♥s ♥ t 2 ♥st♦♥ ②r

r t ①ss t♦ ♦ t ♣sst♦♥ ②r ♦r♥t♥ r♦♠ tt♦r♥ ss ts ♥♥t r♠♦ r♦♠ t tr♦ r t ♠♣t♦ t ♣♥♦♠♥ ♦♥ t ♥ stt ♦ t s♠♣ ♦ 2 rt② t♦♣ t♥t♦♥ ♥ t ♠ ♥ t ♦♥ rt② ♦♥ ts t ss s♦rtrt♥ ♦ tss s t rr♥t ♦s rt② t♥ t t♦♣ ♥ t ♦tt♦♠ tr♦s

t♦r♥ ss ♥ s♦♠ ss t t♦ ♣r♦ss s t♦♦ s♦ ♦r ♥♦ts♥t ♥♦ t♦ r♠♦ t ♣♦t♦rsst t t 2 t♦♣ ♥♥② ♦st♥r t♦ ♣r♦ss s s ♠♦st② ② ♥♦rrt ♥t♦♥ ♦ t ♦r♥

Page 108: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P ❱

r♥ t ♣♦t♦t♦r♣② t t ♣r♦♠ s s♦ ♥♦t t♦ rt t♦ ♥♦ t ♣♦t♦rsst ♥ s ss ♣ t♦ ♦♥ s♦♥ s♦rt trs♦♥ ♣ss r s ♣r♦r rst② ♥rs t t♦ s♣ t s ♥ ♥sr 2

t♦ r♦♠ t s♠♣ sr s s r♠♦ s strt♥ r♦♠ t s♦ t 2 ②r s ♥♦r♠② r r♦♠ t r ♦r tt♦r♥ s ♣r♦r♠ r♥ t st♣ t t♦r♥ ♦ ♦s t♦ tt s♠♣ r♦♥ ♥ t ♠② ♦♥t♥ rsst rss t♦ r♣t♥st♦♥ t 2 s ♣rtr② r t tt ♣♦♥t ♥ t 2 t♦ ♠②ts ♣r♦ r♦♠ t s ♥ s t 2 t♦ r♠♦ r♦♠ t s♥st r ♦r ts rs♦♥ t t♦r♥ st♣ s s ♦♥② rs♦t♦♥ ♦ t ♣ttr♥ ♣♦t♦rsst ♦ ♥♦t ♦t♥ t♦t t

P ❱ t③t♦♥

r t♦r♣② st♣ ❱ s♠ t ❩ ♣♦t♦rsst trst ♦♣♠♥t ♠t ②r ♣♦st♦♥ ♥ strtr tr t t♦ ♥ t t♦♣ ♣tr t s♠tr♥s♣r♥t r ♦♦r ♦ t ♣♦t♦rsst sst② tr ♥ ♦rr t♦ s♦ tt tr r r♥t ♠trs ♥r♥t

❲t t t ♦♥tt rs ♦r ② t 2 ♥st♦r ♦tt♦♠ tr♦ss ♣s ♥ ♦♣♥♥s t♦♣ t ♥t♦♥s r♠♥ ①♣♦s ♠t③t♦♥s ♥② ♣r♦r♠ s s ♦♥ ♥ s♠r ② t♦ t ♦r♠r st♣ s♥t s♠ ❩ ♣♦t♦rsst ♦♥② ts t♠ t r♠♥♥ rsst s ♣rsr ♦r t s♠♣ sr ①♣t t rs r t ♦♥t ♦♥tt ♣s r♠♥t t♦ ♣♦st s♠♣ s t♥ ♠♦ t♦ t Pss②s ♠t ♣♦rt♦♥ s②st♠ r ♥♠♥♠ ②r s♣♦st ♥r s ♣rssr ss t♥ 9 · 10−7 ♣♦st♦♥ s♣s♦r ♥ r s ♥ s rs♣t② trrs t s♠♣ ♥r♥tt t♦ ♣r♦ss ♠ sr t ts st♣ s r ♣♦t♦rsst rs t♦ ♠♠♦r s② t♥ t s♠ ♦♥s trrs ♦♥② t ♠t ♦♥tts r♠♥

Page 109: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P

r ♥ ♣tr ♦ ♣rt ♦ ♦rrt② ♣r♦ss s♠♣ t♠trs rs♣t ♦♦rs r strt ♦r t ♥♠ t2 t ♦tt♦♠ tr♦ ♦r t t 2 ❨♦ ♠t②r ♥t♦♥ ♣rs ♥ ♦r tr♦ ss ♣s ♥ r② s♥ ② st♦♥t♦rs ♣rss♦♥s ♥ t ②r ♦♠♣r t ♥

♦♥ t s♠♣ s ♣rs♥t ♦♥ ♠♥♠ s ♣♦st s t ♦r♠t③t♦♥ ②r t♦ ts ♦♦ s♦♥ ♣r♦♣rts t♦ t ♣sst♦♥ ②r ♦ s ♦s♥ s t ♥ t♦♣♠♦st ②r s t s r② r t♦ ♦①③ ♣tr♦ t t♦r♣② ♥ rst s s♦♥ ♦♥ t

sst♥ ♣r♦♥ ♥ ♦♥tt ♠♦s

s tr r ♥t♦♥s ♣r ♣r♦ss s♠♣ t s ss♥t t♦ ♥ ♦t ♦♥s ♦ st ♦r rtr ♠sr♠♥ts s ♥t rsst♥sts r ♣r♦r♠ t♦t ♦♥♥ t s♠♣ ♦r ♣♥ t ♥ ♠♥t s s ♦♥ s♥ r ss P ♣r♦r t ♦♥ ♥ ♣r♦r♠q ♠sr♠♥ts ♦♥ ♠♥② ♥t♦♥s

Page 110: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P ❱

♦♣♦♥t ♠sr♠♥t ♦ t ♦♥tts

rsst♥s ♦ t♦♣ ♦♥tts ♥ ♦tt♦♠ tr♦s r rst ♥ t st♥r t♦ ♣♦♥t ♦♥rt♦♥ ♥ ♦rr t♦ ♥sr tt tr rsst♥s r s♥t②s♠ s♦ t② ♦ ♥♦t ♦rs♦ t ♦♥s ♦ t ♥t♦♥s ♦♥r♥♥ s♠♣s♣r♦ss t t ♦♣t ♣♦t♦t♦r♣② t t♦♣ ♦♥tts rt♦♥ ♦♥t♦♥sr♥ t ♦rt st♣ r t s♠ ♦r t s♠♣s ①♣t t ♣♦st♦♥ ♣rssr ♦ tr ♥s♥♥t② s t rst t② ②s ② r♦♥10Ω rsst♥ ♦ t ♦tt♦♠ tr♦ ♣♥ rt② ♦♥ t s♠♣strtr ♥ ts t♥ ♣t tr t rst t♦r♣② st♣ t t s② ②t♥ Ω ♥ Ω ♥ s ♦ ♥st s♦♠s♣ttr♥ ②r ②st♠s♠♣s ♦t ♦tt♦♠ ♥ t♦♣ tr♦s r st♦♠♣♦st s♦ tr rsst♥sr ♠♦♥ s♠♣s t t② rr② ① Ω

♦r♣♦♥t ♥t♦♥ st②

r ♠t strt♦♥ ♦ t ♣♦♥t ♦♥tt ♠sr♠♥t ♦ts ♣♣ t♥ t♦ ♦♥tts ♦♥ ♣♣r ♥ ♦♥ ♦r ♥ t rr♥t ♦ s♠sr t♥ t ♦tr t♦ t② t rr♥t s♥s s t rr♥t ♦♥tr♦ t r♦ss♣♦♥t ♦♥② ♥ ts s t ♠♥t t♥♥ ♥t♦♥

♥ t ♦♥tt rsst♥s r ♥♦♥ t ♥t♦♥ t♠ss ♥ ♣r♦ ♥t ♣♦♥t ♦♥rt♦♥ s s ♦r♠ ♦ ♠sr♠♥t s t ♥t♦r t t♦♣♦♥t ♠♦ tt t ♠srs ♦♥② t rr♥t ♦♥ tr♦ t r♦ssst♦♥ ♦♠tt♥ t rsst♥ ♦ ♦♥tts s ♦s ♣rs ♥t♦♥ st② ♥s ②s ♣rrr rtr t♥ t t♦♣♦♥t ♠♦ ♦r ♠tt♦♥s ♦ ts♠t♦ ①st

t ♦♥tt rsst♥ s ♠ rr t♥ t rsst♥ ♦ t r♦ssst♦♥♥ ts s t ♥t♦♥ ♥t rsst♥ ♥ rtt ♠② ♠sr ❬❪t s ♦r ts rs♦♥ tt t ♦r tr♦ rsst♥ s ②s ♠ t♦ s♦ s ♣♦ss ② ♦r ♥st♥ ♥♦t ♦rt♥ t ♦r tr♦ s sr ♥st♦♥ ♦♥tt rsst♥s ♠② s♦ rst r♦♠ tr ♠♥♠ ♥ ss ♦ ♥t♦♥s ♦r t r ♦ t ♦♥tts ♦ ♥♦t ♣t② t♦ ♠sr ♥ t st♥r ♣♦♥t ♦♥tt ♦r ♥ ss ♦ ♦♥

Page 111: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P

r strt♦♥ ♦ t ♣♦♥t ♦r ♣♦♥t ♦♥tt ♠sr♠♥t ♣r♦r♠ ♥ s ♦ t tr♦ ①ss rsst♥ ♦r ♠ s♠t② ♠rs t r rsst♥ ♦ t t♠♦st ♣rt ♦ t tr♦ ♦♥ t ts ♦♥tt r s t♦ t ♥t♦♥ rsst♥

♦♥♥t♦r ♦♥② ♥ t ♣♦♥t ♦♥rt♦♥ s♦♠t♠s rrr t♦ s t ♦r♣♦♥t ♦♥tt

sst♥r ♣r♦ts

♥t♦♥s rt r♦♠ t s♠ s♠♣ r ①♣t t♦ s♦ s♠r rtrsts r♦♠ ♥♦♠♥ r♦t st♥♣♦♥t t ♥st② ♥ q♥t③t♦♥ tss t ♦♥② r②♥ ♣r♠tr s tr r s rsst♥s ♦ ♥t♦♥s t♥t s♠ r♦ r ①♣t t♦ ♦ t s♠ ♦rr ♦ ♠♥t t♦ tr s♠s③ s♠r ♥t♦♥s s♦ s♦ ♠ r s ♦ rsst♥ ♥ ♦rr t♦ ♥♦t tr ♦sr rsst♥s r sttst② ♦rrt tr sst♥r♣r♦ts r ♦♠♣r t s ♦♦s

RA = R ∗ A[µΩm2]

♦rrt② ♣ttr♥ ♥t♦♥s s♦ ①t ♥ ♥♦r♠ ♣r♦t ♦r ts♠♣ ♦r s ♣rs♥t t♥ t s♠♣ ♥②ss s♠ ♥t♦♥st♥ t♦ s♦ tt s ♠ r t♥ ①♣t s s s ts♠st µ♠ ♥ ♠tr ♥t♦♥s r r t♦ ♦t♥ t♦ t t t♦r♣②rs♦t♦♥ ♥ tr s③ s s② s♠r t♥ ①♣t t♦ t s♠ s③ ♥st rt♦♥ ♥ t ♥t♦♥ s③ s t♦ t r ♥ ♥ t ♣r♦t ♦rrt② rt ♥t♦♥s r ss♠ t♦ t ♦♥s ♥ tr t♥ t s♠ ♦rr ♦ ♠♥t st② ♦ t♦ q② st s ts r tr s♦rt r② ♦ ♦r ♦♣♥rt t ♦♥s r♦♠ t ♣♦t♦rsst s ♥♦t r♠♦ tr♦♦t t t♦ ♣r♦ss s♥ ♥♦rr♥t ♦ ♥ s♠ ♣ttr♥s ♦ t ♣♦t♦rsst r t t♦ r♠♦ r♥♠r ♦ t s♠st ♥t♦♥s ①t t ttr ♣r♦♣rts

Page 112: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P ❱

♠♦♥ s t

r ♠♦♥ s tt♥ ♠♣t ♦♥ t rsst♥ r ♣r♦t ♦ sr♥t♦♥s sqrs ♥ r rs s♦ ♣r♦ts ♦ ♥t♦♥s ♦r ♥tr tt♥ t s♠♣ rs♣t②

♦r ♥② ♥ ♠sr♠♥ts t s♠♣ ♥s t♦ ♠♦♥t ♦♥ tt rt ♣ s st♦♥ ♦r ts ♥ ♦rr t♦ ♦ s♦ ts s③ t♦ r ② tt♥ s♦ t ♦ t ♦♥ t ①♠♠ s♥t ♣ r ♦ ♣r♦ttt s♠♣ sr r♦♠ ♥② ♦♥t♠♥t♦♥ rst♥ r♦♠ t tt♥ ts srs ♦r t t ❩ ♣♦t♦rsst t♦t ♥② rtr ♣r♦ss♥ ♥ ❲ ♣rs ♠♦♥ s s s ♥ ♦rr t♦ r♠♦ t ♦tr ♣rts ♦t s♠♣ r♦♥ t r t♥ t ss♥t ♣rt s t ♥ t♦ ♦♥ t ♦r③♦♥t s♣r t♥ t t♦♣ ♥ ♦tt♦♠ s ♣♦t♦rsst s t♥r♠♦ ♥ t st♥r t♦♥ ♥ t♥♦ t t♦t t trs♦♥s s♥t♦ ♦ s♦ ♦ t t 2 ♥ s♦♥ ❲ ♦♥r♠ tt ttt♥ ♣r♦r ♦s ♥♦t t t ♣r♦♣rts ♦ t ♥t♦♥s

r Ptr ♦ t t s♠♣ ♠♦♥t ♦♥ t rt ♣ t ♥t♦♥s♦♥ t ♦tt♦♠t tr♦ ♦♥ ♥ t ♦r♣♦♥t ♦♥tt ♠♦ ♦♥♥ rs♦♥♥t♥ t ♣ ♥ ♣s r s

Page 113: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯ ❲

♥♣ ♠♦♥t ♥ r♦♥♥

s♠♣ t ♥♦ ♦ ts ♦r♠r s③ ♠② ♥ ♦♥ t♦ t ♣ ♦♥r s t♥ t t♠r♠ ♦ ts tss s t ②♦♥ tr♠♦s♦♥ ♦♥r ♥ ts ♦♥♥ t♥q t ♠♥♠ r s t♦ ♦t s♠♣ ♥ ♣ ♦♥ ♣s ② ♣rssr ♥ trs♦♥ ♦st rt♦♥ ♠t♦ ♦s ♥♦t rqr ♥② t ♥ ♦rr t♦ rt t ts t s ♣rrr t♦ ♦♥♥ s s♦ t t t♥♦ ♥r♦♦♠ ♥ ♦rrt♦ ♦ ♥② str② rr♥ts t♥ ♦ ♠ t ♥st♥ rrr t s♠♣s tr② r♦♥ r♥ t ♣r♦ss s♠♣ ♦♥ ♦♥ t ♣ ♥ t♣♦♥t ♦♥rt♦♥ s ♣rs♥t ♥

Page 114: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P ❱

Page 115: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♣tr

st② ♣♣rts ♥

t♥qs

s ♣tr srs q♣♠♥t ♥ s♦♠ ♦ t ♠sr♠♥t t♥qs st♥ t t♠r♠ ♦ ts tss t ♦♥♥trts ♦♥ t rt st♣ ♥ tst ♣ ♣r♦♣rts rst st♦♥ ♥ ♦ t s s ♥ ♦rr t♦ ♦t♥ I rtrsts ♥ ♦tt♠♣rtr ♣♥♥② ♠♣s st♦♥s ♥ ♦rtst♦♥ ♣rs♥ts t ♦♣t st♣s s ♥ ♦rr t♦ ♦t♥ t ♣♦t♦♠♥s♥♥ s♦r♣t♦♥ s♣tr

st♣ ♣ts

♦♥strt♦♥ ♦ t rt ♣ ♣rs♥t ♦♥ ♣ ♠s t ♣♦ss t♦ ♦♥♥ ♠sr ♣ t♦ ♥t♦♥s ♥ ♣♦♥t ♠♦ ♦r ♣ t♦ ♥t♦♥s ♥ ♣♦♥t♦♥rt♦♥ ♠sr ♥t♦♥s sr t ♦r tr♦ s ♠s ♥t♦♥♥ st♦♥ s♠♣ r♠♦ r♦♠ t ♣ s s② ♥♦t ♣♦ss t♦t♠♥ t t ♣♦sst② ♦ ts ♠t♣ r♦♥♥ s rt ♥t♥ t ♥♠r ♦ ♥t♦♥s ♣r s♠♣

rt ♥ ♦s t♦ ♣r♦r♠ ♠t♣ s♠ ♦r ② t♦♠t ♠sr♠♥ts q♣♠♥t ♦s t s♠♣ t♦ ♠♦♥t t♥ t r②♦stt ♣t♥ tr♦♠♥t ♦s t♦ ② t ♠♥t ♦ ♠♦r t♥ r②♦stt ♥ t q ♠ r♦♠ ♥ ①tr♥ s♦r ♥ ♦♦♦♥ t♦ ss t♥ t♥s t♦ ts t♦♠r s♥ r♥ t t♠ ♦ tstss st♦♠♠ ♣♦r s♦tr s ♦♣ ♦s t♦ ♣r♦r♠ t♦♠t t♠♣rtr♣♥♥t ♠sr♠♥ts t st t♦♠t st♥ ♠♦♥ s ♣♣ s ♦t ♥ ♠♥t s ♥t♦tr♥s♣♦rt♠sr♠♥ts ♥ ♣r♦r♠ ♦r ♠t♣ s♠♣t♦ ♥s ♥② rr♥t♦t rtrsts r t♦r ♥rst♥♥ t t ♥r② s ♥ ♦t♥ ♦r r♥t t♠♣rtrs ♥ rt ♠♥t③t♦♥ ♦r♥tt♦♥s ♦ trr♦♠♥t tr♦s ♥t② s♠t♦♠t ♠t♣①♥ s ♣r

Page 116: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❱ ❯❨ PP❯ ❯

t♥ t rt♦♥ ♦ ts tss t♦ t ② t♦♠t ♥t♦♥t② t ♦r ♦❯ s♠r ♦ st st♥ t♥ ♥t♦♥s r♥ t ♠sr♠♥t ♥♥ sttst ♦♠♣rs♦♥ ♦ t ♥t♦♥s ♦r ♥r ♦♥t♦♥stt ♠t ♦trs ♠♣♦ss t♦ ①t② r♣r♦

①♣r♠♥t tr♠♥t♦♥ ♦ t rrr ♣♦

t♥t ♥s♣

♦♠♣tt♦♥ t♥qs t♦ tr♠♥ rrr ts s ♦♥ t r♥♠♥s ♦r♠♠♦♥s ♦r♠s ♠♥t♦♥ ♥ st♦♥ sr r♦♠ sr♦s r trt② ♦♥② ♦r t rrrs Prs♥ ♦ ♠t♣ t②♣s ♦ ts s st♦♥ t♦♥ ♥tr ♦① sts ♦r ♥ tt♥ ♣r♠trs sss ♥ rs t♦ sr♣♥② t♥ rsts ♦ t♦♥s ♥ rt②

rt ❱ rtrsts ♥②ss

♥ rr♥t♦t rtrsts r ♥♦r♠t♦♥ rr♥ ♦t t ♦♥t♥ rss s♥♥t② t V/e s t ♥r② ♦ t ♦♥t♦♥ ♥ ♦r t rt② t♦ t r♠ e ♥ t tr♦♥ ♠sss ♣♣r♦ s s ♥ ♥②ss ♦ rrrs ♥ st♦♥

g ♠t♦

♦tt♥r t ♣r♦♣♦s t♦ ①♣r♠♥t t♥qs t♦ ♠sr t rrr t♦♥ s ♦♥ t ♦rt♠ rt ♦ ❱ rs ♥ ♦♥ s ♦♥ t t♠♣rtr ♣♥♥ ♦ ts rs ❬❪

r ♠t r♣rs♥tt♦♥ ♦ t rrr ♦r ♣♦♥ ♣♣②♥ s s ♦r ♥ r t♥ t rrr t rs ♣t t r♥♠♥stt♥ t② ❬❪

Page 117: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯

r s♠t② s♦s t ♦r ♦ ♣♦t♥t rrr t qts t ♥tr tt s ♦ts t t♦ r♥t ①tr♥ ♦tr♥ ss t ♣♣ ♦t V +dV s ♦r t♥ t rrr t t rrrr t rss ♦♥ t t dV ♦t ♥rs t ts t r♠♥s♦♥st♥t ♦r t V + dV ①s t rrr t t dV s ♦t♥r♠♥t ss ♥♦t ♦♥② rs ♦ t t r rrr t t ♦ tst s ♥ t♦ ♥ t♦♥ ♠♦r ♣r♦♠♥♥t rs ♥ ♥t♦♥ ♦♥t♥

I ♠t♦

s♦♥ ♠t♦ ♣r♦♣♦s ② ♦tt♥r t s ①t♥s② s t♥ tt♠r♠ ♦ ts tss t rqrs ♣r♦r♠♥ rr♥t♦t rtrsts tt♦ r♥t t♠♣rtrs s t r♠ strts t♦ s♠r ♦t t t ♥rs♥ t♠♣rtr t rr♥t t♥♥s ♠♦st ♥t② ♦r ♦ts st ♦t rrr t ♦ t ♣♦st② s tr♦ ♥♦r♠③ t♠♣rtr♣♥♥ ②s ♥rs s r♦♥ t rrr t ♦ t ♣♦st②s tr♦

I(V ) =I(V, T2)− I(V, T1)

I(V, T1)

♠sr♠♥ts ♦♥ ♣r♦r♠ ♦♥ r♥ ♦ t♠♣rtrs IT1−T2

IT2−T3 IT3−T4

♥ s♦ ♦♥ ♥ ② ♥st ♥t♦ t tt♦♥ t♠♣rtr ♥♦t ♦ rt♥ ♠♥t♦tr♥s♣♦rt trs ② r rt I ♦r Irel s♦♣♣♦s t♦ s♦t I ♦r Iabs srs ♥ t t s ♣♦tt ♥ rr♥ t♦ ① s② ♦ t♠♣rtr

❱♦tt♠♣rtr ♣♥♥② ♠♣s

ts tt ♥♥ t ♠♥t♦rsst rtrsts ♦ t st s②st♠s rstr♦♥② ♣♥♥t ♦♥ ♦t ♥ t♠♣rtr rt♦♥s ♥ ♥ ♦rr t♦ ♥rst♥ ts ♣♥♥s ♦♥ ♥s t♦ ♥②③ t♠ t♦r♦② ♥s t♦ t♣rt t♦♠t♦♥ ♦ t rt st♣ ♠sr♠♥ts r♥ t ♥ ♣rt ♦ tt♠r♠ ♦ ts tss ♠t♣ ♥t♦♥s ♦ st ♣♦♥ s♥ srs♦ ♦t ♥ t♠♣rtr s♣ s ♦ t♦ rt t♦ ♠♥s♦♥ ♦tt♠♣rtr ♣♥♥② ♠♣s ♦ rsst♥ ♠♥t♦rsst♥ ♥ ♦t s♦t♥ rt I s

♣t sts

♦♣t sts ♦ ts r ♣r♦r♠ ♥ ♦r r♦♣ t♥s t♦ ② ♠rr s s ② t ♦t r♦♣ t♥ ♣rt♠♥t ♣tq trr♣ t

Page 118: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❱ ❯❨ PP❯ ❯

♥♦♣♦t♦♥q r♦♣ s rst ♦ ♥ ♥tr♥ ♦♦rt♦♥ t♥ tP ♦t r♦♣s ♦♣rt st♥t t②♣s ♦ ♦♣t st♣s t r♥t ♣ts st♣ ♦♣rt ② ♠rr ♦♥sst ♦ ♥♠ ①tt♦♥ ♥t ❨ ♥♦②♠♠ ♦♣ ❨3512 sr t ♠❲ ♣♦r r ♦t ♦♣t sts r ♣r♦r♠ ② tt rt r♦♠ t ♦t r♦♣ s♥t ♥♠ sr st♣ ♣ ♦ ♣r♦r♠♥ t♠♣rtr ♣♥♥t sts② ♣♥ s♠♣s ♥ t r②♦stt ♥ ♥ t t t q ♠ ♦r♦r s♦r♣t♦♥ s♣tr st♦♥ r ♦t♥ t ❯❱❱s Pr♥♠r♠ s♣tr♦♣♦t♦♠tr ② ❲ ♦ r♦♠ ♦ t♦♥ ❯♥rst② s rst ♦ ♥ ①tr♥ ♦♦rt♦♥

Page 119: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

Prt

st②

Page 120: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue
Page 121: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♣tr

r♥st♦♥ ♠t ♦①s

r♥st♦♥ ♠t ♦①s r ♦ rt ♥trst t♥ t ♦ s♣♥tr♦♥s t♦tr ♣♦t♥t ♠t ♣r♦♣rts s t ♦♥s r♣♦rt ♥ 0.7r0.3♥3♦r♦r t♦ ♦ ♥♣ ♦ r3 ♥ 2 r②sts r♦♥ ❱ t②r ♥♦t s t t♦ st② ♦♣t② s tr ♦♥tr♣rts ♦r ♣ ❯❱ sr s ♥ ❯s♥ rq♥s ♥♦ t♦ ♦r♦♠ t ❱ ♣ ss s♦r♣t♦♥ ♥ ♠♥s♥ r♦♠ srr♦♥♥ ♠♥ts ♥ t s ♦tr♥st♦♥ ♠t ♦① rrrs st② t ss s ♣rs♥t t♦ ♠ ssr ①t♥t

♥ s ♦ ①♣r♠♥ts ♣r♦r♠ ♦♥ tr♥st♦♥ ♠t ♦①s s♦♥ s♠♣ ♦ ♥ s r♦♥ t♥ ♣r♦ss t t st♥r t♦r♣②♣r♦rs sr ♥ st♦♥ ts ②♥ ♣ t♦ s s sr st ♥ tr♠s ♦ tr ♣r♦ts ♥ ♠♦♥ t♠ rt♥ ♥♠r s♦s♥ ♦r ①t♥s sts

tr♦♥t♠ tt♥t

s ♠♥t♦♥ ♥ st♦♥ rrr ♦♠♥ t tr♦s s♦t st s s♦ r ♦r t qst♦♥ r♠♥s tr t s ♣♦ss t♦ ♦t♥ tr♥st♦♥ ♠t ♦① s ♠♥t t♥♥ ♥t♦♥s t s♠♣tr♦s s♦ tt ♦♥ ♠② ♦♠♣r t t♦r② ♠♦r s② ❬❪

♦♣t tt②

♥ ♦rr t♦ ♣ t ② ♦r tr sts ♦♥ t t♠t s♣♥ ♣♦r③tr♥s♣♦rt ♥ ts ♣r♦♣rts ♣♦♥ ♠♥t♦♥ ② sr t sr ♠sr♠♥ts r ♣r♦r♠ s♦s t ♣♦t♦♠♥s♥ ♦ ♥♦♥rrt ♥r+ rrt r3 r②sts ♠♥t t ♥♠ sr ♥♠ ♣ ♦ ♥♦♥rrt r②st s ♦♠♠♦♥② ♦sr ♥ st♦♦♠tr r3 ♥ rts r♦♠♥t♦♥ ♣r♦ss ♦ ①t ♦s ♥ tr♦♥s t str♣♣ ①t♦♥s ❬ ❪ ♥

Page 122: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❳

r ♠♣t ♦ r+ rrt♦♥ ♦ r②sts ♦♥ t ♣♦t♦♠♥s♥s♣tr t s ♦t tr ♠♥t♦♥ t t ♥♠ sr

r P♦t♦♠♥s♥ s♣tr ♦t r♦♠ r②st t ♦r ♠♥ts ♥ ♣♣ t ♥♠ ♦r ♥♠ s ♥s r♣rs♥t ♣♦st♦♥s♦ ♣s ♣♣r♥ ♦r s♠♣s ♣rs♥t ♦♥

Page 123: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

t ♦tr ♥ t ♥♠ ♣ ♦ t rrt r②st ♦rrs♣♦♥s t♦ t r♦♠♥t♦♥ t♥ ♦♥t♦♥ tr♦♥s ♥ ①t ♦s ♦♥t♦♥ tr♦♥♥st② ♥rss t ♥rs♥ ♦①②♥ ♥② s t♦ r ♥♠♠♥s♥ ♥t♥st② ❬❪

♥ t♦♥ st② s ♣r♦r♠ ♦♥ s♠♣ rrt ♦r ♠♥ts s♠♦rt② t s♠♣ s♦s ♣rt trs ♦ ♦t t r♥ ♦♥ ♥ t♦♥ ♥♥ ♦r ♠♥ts ♥ ♣rt ♦ t s♠♣ s ♣♣ t♣♦rt ②r ♦ ♥♠ rs t ♦tr s ♣♣ t ♥♠ ss♦♥ ♦♥ t t P s♥ ♥ r ♥ tr♦ t rt② t♥♠ ②r ♦ ♦

r ♠♣rtr♣♥♥t ♣♦t♦♠♥s♥ s♣tr ♦ r②st rrt ♦r ♠♥ts ♥ ♣♣ t ♥♠ ②r t s ♦t trt ①tt♦♥ t t ♥♠ sr

①♣r♠♥t ♦ t♦ st♠t t t♥ss ♦ t t♦♣ tr♦ s ss♥t ♦r ♣♥♥ tr ①♣r♠♥ts ♥♦♥ ♠♣t ♦ t sr t ♠♥t♦♥ ♦ ♥t♦♥s ♦♥ tr tr♥ s♣♥♣♦r③ tr♥s♣♦rt ♥ ♦rr t♦tr♠♥ tr t♠♣rtr♣♥♥t ♦♣t ♣r♦♣rts ♦ t ♣♣ r②st♦ ♠sr sts t ♦ t♠♣rtr r ♣r♦r♠ ♦♥ s♠♣ rrt ♦r ♠♥ts ♥ ♣♣ t ♥♠ ②r s♣tr♠s♦s ♣ t ♥♠ ♣♦♥ ♦♦♥ ♦♥ t♦ s♣ts ♥t♦ ♥♠ ♥♥♠ ♣s ♦r♦r t ♣♦st♦♥ ♦ t ♠♥ ♣ t s ♥♠ rsttr s ttrt t♦ t r♦♠♥t♦♥ ♣r♦ss t♥ ♦♣ ♦r ①t

Page 124: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❳

tr♦♥s ♥ ①t ♦s tr♦ t rs t s♦♥ ♦♥ ♦rrs♣♦♥st♦ r♦♠♥t♦♥ ♦ ①t ♦s ♥ tr♦♥s ♥ str♣♣ ①t♦♥ s st♦♥

♦2r3♦2

r ♥ st ♠s t♥ ♦♥ t ♦ s♠♣ tr t ♦2♥♠ ♥ ssq♥t r3♥♠ r♦t ♣trs r t♥♦♥ t ❬❪ sstrt ③♠t ❬❪

♥ ♦rr t♦ st② t t♠♣rtr ♥♥ ♦♥ ts ♦r♠t♦♥ ♥ t ❬❪ s s ts ♥♥ ♦♥ t ♦2r3 ♥tr st t t♦2♥♠r3♥♠♦2♥♠♥♠♥♠ strtr s r♦♥♦♥ t sstrt ② t ♣s sr ♣♦st♦♥ t♥q ♥ ♦♥t♦♥ssr t♥ st♦♥ ♦r ♦2 ②r s r♦♥ t rst r3 rrr s r♦♥ t ♦ s♠♣ ♥ s♠♣ ♦2 t♦♣ ♠♥t ②r s r♦♥ t ♥ ♣♣ t r♦♥ t♥t♠ ②r ♥ ♦rr t♦ ♣r♦tt t s♠♣ r♦♠ ♦①t♦♥ ♣♦st♦♥♣rssr s ♠♥t♥ t 2 · 10−7 ♠r ♠sr♠♥ts ♣r♦r♠ ♦♥t ♦ s♠♣ ♦t tr t ♦r ♦2 ♥ t r3 rrr r♦t s♦♦rrt r②st♥ strtr ♦ ♥trs

♠r♦r②st♥t② ♦ ②rs ♥ tr rs♣t ♦r♥tt♦♥ r tr♦ rs♦t♦♥ tr♥s♠ss♦♥ tr♦♥ ♠r♦s♦♣② ♠sr♠♥ts rs t ♦r♠t♦♥ ♦ r② ♥♦r♠ ♥ strtr② sr♣ ♥trs ♦ ♥♦ t r3 rrr rrr t♥ss st♠t r♦♠ t ♣tr

Page 125: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

r rs♦t♦♥ r♦ssst♦♥ ♦ t♦2♥♠r3♥♠♦2♥♠♥♠ ♦ st t♦♣♠♦st ②r s ♥♦t s♦♥ ♣tr s t♥ tt ♦ s t t ♣♦♥t rs♦t♦♥ ♦ ❬❪

s 3.1± 0.2♥♠ t♦♠ strtr ♦ ♦t t ♦tt♦♠ tr♦ ♥ t rrrs ♠♦♥♦r②st♥ s ♦sr ♦♥ t s♣tr ♥ t ♦tr ♥ tt♦♣ ♦2 tr♦ s ♣♦②r②st♥ t t t♦♠ ♣♥s ♥♦t ♥ ❲ttrt ts t♦ t ♦ r♦t t♠♣rtr ♦ ts tr♦

♦♦♠t♠♣rtr tr♥t♥ r♥t ♠♥t♦♠tr ♠sr♠♥ts ♣r♦r♠ ♦♥ ♦t s♠♣s s♦ sr♣ rrs ♦ tr♦s ♠♥t③t♦♥s♥ ♦r s ♦ ♥ ♦r t ♦ st ♥ ♥ ♦r t st ♠♥t s ♣♣ ♦♥ t sstrtrt♦♥ s♠r ♥ rr ♦r s ♦rrs♣♦♥ t♦ t ♠♥t③t♦♥ st♥ ♦ t ♦tt♦♠ ♥ t t♦♣ tr♦ rs♣t② st rs ♦ts s ♦r t s♠♣ ♠② ttrt t♦ t ♥tr ♦①t♦♥

Page 126: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❳

r r♦♦♠t♠♣rtr ♠sr♠♥t ♦ t♦2♥♠r3♥♠♦2♥♠♥♠ ♦ ♥ ♠t②rs ♦♥ t ❬❪ ①s ❬❪

♦r t s♠ rs♦♥ t ♦ ♣♦st♦♥ rsts ♥ st② sr♣r r r♦♦♠ t♠♣rtr s ♥♦t ♦sr ♦r t s♠♣ t

♦ ♦♥ ② ♣♦st rsst♥ r ♣r♦t ♦ts ♥t♦♥s s ♦ 105µΩm2 r♥ st♥ s r ♥ r♠♥t tt ②strss rs ♦t♥ r♦♠ ♠sr♠♥ts

r r sr rs♦♥s ttrt t♦ t ♦ ♦ t t♥♥ ♠♥t♦rsst♥ rt♦ ♦r t s♠♣ ♥ t r3 rrr s r♦♥ t t ♦rt♠♣rtr ♦♥ ♥②③s t rrr ♥ strtr t s s② t♦ s tttr♦♥s tt ♦♠♥♥t② t♥♥ r♦ss t rrr r ♠♦st② ♦ t ∆2′ ♥ ∆5

s②♠♠tr② ♥ t s ♦ r♦♥ tr♦s ♥s ♦ ts s②♠♠trs r♦sst r♠ ♦r ♦t ♠♥♦rt② ♥ ♠♦rt② tr♦♥s ♣♦♣t♦♥s rst♥ ♥♣♦♦r tr♥ ♥ t ♦tr ♥ ♥ ♦t ♥s ♦ t ∆2′ ♥ ∆5 s②♠♠tr② ①st♦♥② ♥ t ♠♥♦rt② s♣♥ ♥♥ ♦ ♥ strtr ♦rs ♥s♥t② ♦tr ♦ ❬❪ ♠② ♥♦t t s ♥ ♦r ♦2 strtrs♦x1−x x = 0.5

♥♦tr t♦r tt ♠② r ♠♣t ♦♥ t ♦ rt♦ s t rrr strtr t t ♥tr s sr ♥ t t♦rt ♣rt t r3

♠♦♥♦r②st♥ rrr ♦♥sst ♦ tr♥t♥ r ♥ 2 ♣♥s s st♦♥

Page 127: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

r ♦♦♠ t♠♣rtr r ♠sr ♦♥t 20µ♠ ♥ ♠tr ♥t♦♥ ♣r♦ss r♦♠ t ♦♦2♥♠r3♥♠♦2♥♠♥♠ st❬❪

t♦ ♥ ①♣r♠♥ts ♦♥r♠ t ♣t① strtr ♦ t rrr t ♥tr t♦♠ st♣s r ①tr♠② r t♦ ♦ ♥t rs♦t♦♥ ♠r♦s♦♣② ♠ ♥♥♦t ♥t ♥sr s trtr s ♦♥② ♦♥ t②♣ ♦ t ♥tr tr♠♥t♦♥ ②r ♦r ♥♦t s s♦♥ ② ❱rr♥ t t s♥ ♠② ♣♥ ♦♥ t tr♠♥t♦♥ ②r ❬❪ s♠② t s ♥ t st s②st♠ ♥ t ♥tr ♠② ♦♥sst ♦ tr ♥ 2 ♠①tr ♦s ♣♦st ♥ ♥t s♣♥ ♣♦r③t♦♥s r ♦t♥ rst ♥ rt② ♦

rs♦♥ ♦r t t♥♥ ♠♥t♦rsst♥ s ♥♦t ♦sr ♥ t s♠♣ ♦ t rrr ♣♦st♦♥ t♠♣rtr ts ♦r t r ♥r②♦ t♦♠s r♥ t r♦t ♦rs t ♦① ♦r♠t♦♥ t t ♦tt♦♠ ♥tr♥♦t② t r♦♥ ♦① s ②♣♦tss s s♣♣♦rt ② s♦♠t rr ♦rs ♦sr ♦♥ t s♠♣ ♥ t ♦tr ♥ t ♦ s♥♦sr ♥ t ♦ s♠♣ ♠② rst r♦♠ t s♠ ♦①t♦♥ ss s t s♣rssr ♥ t P ♠r ♣r♦r t♦ t ♣♦st♦♥ s t♥ t 10−8 ♠r r♥s st♦♥

♥ ♦rr t♦ rtr ♦♥r♠ t ♦①t♦♥ ②♣♦tss t rr♥t♦t rtrst s ♣rs♥t rrr ts t ♦t ♥trs r t s♥ t

Page 128: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❳

r ♦♦♠ t♠♣rtr ❱ ♠sr♠♥ts ♦♥ ♥t 20µ♠ ♥ ♠tr♥t♦♥s r♦♠ t ♦ ♥ sts t ♥ ♦rrs♣♦♥♥ ♦♥ ♦t♣♥♥ ♦r t ♦ ♥t♦♥ rt ♦ ♠♥t♦rsst♥ s ♣rs♥t ♦♥ t ♥t♦♥ ♥♦t s♦♥ ❬❪

r♥♠♥ ♠♦ ❬❪ s t♠♣rtr♣♥♥t I ♠sr♠♥ts r ♥♦t t t t♠ r♥♠♥ t ♦ t t♦♣ ♥tr rrr t ♦r ♦t ♥ ♦ s♠♣s s♦ ❱ ♥t s ①♣t ♦r ♦ts♠♣s s tr ♣♣r ♥trs r rt ♥ t s♠ ♣♦st♦♥ ♦♥t♦♥s♥ t ♦tr ♥ rrr ts ♦ ♦r ♥trs r ❱ ♥ ❱ ♦rt ♥ ♦ ♥t♦♥s rs♣t② s s♦s t ♠♣t ♦ ♦①t♦♥♦♥ t ♦r ♥tr s rtr ♥♥ ♦r t t♠♣rtr rrr♣♦st♦♥ t t♥ss tr♠♥ ② t r♥♠♥ t ♦r ♦t s♠♣st s ♥♠ ♦s t♦ t ♦♥ ♦sr ② t ♥♠

s♣t t rt② ♦ s♥ ♦sr ♦♥ tt t s t rstt♠ tt t s♥ s r♣♦rt r♦ss r3 s ♥t♦♥s t s♠♣tr♥st♦♥ ♠t tr♦s ♥②ss ♦ t rsts ssts tt s♥♥t ♠♣r♦♠♥t ♥ ♣r♦♣rts ♦ ♥t♦♥s ♦ ♥ t♦ ②s ② ♦♥tr♦♥ t♦♠♣♦st♦♥ ♦ ♥tr r3 ②rs ♦♥ ♠② ♥sr t t♦♠ tr♠♥t♦♥ ♦t rrr ♥ ♠♥t t s♠t♥♦s ♣rs♥ ♦ r♥t s②♠♠tr② tr♥♥♥s rst ♥ r♥ ♦ ♣♦st ♥ ♥t ♠♥t♦rsst♥ rt♦s sttt♦♥ ♦ r3 t 2 ♥ ♦♠♣s ts ♥tr r♦♥♦① ♦r♠t♦♥ ♠② ♦ ② ♠♦♥ st♦①③♥ ♠♥ts ② ♥tr♦t♦♥ ♦ t♥ ♦t t ♦t ♥trs ♠② s♦ ♠♣r♦ t s②♠♠tr② tr♥ s t♦ r♠♦ ♥s ♦ t ∆2′ ♥ ∆5 s②♠♠tr② r♦♠ t r♠ ♦ tr♦s ♦t ♦ ts s♥r♦s r tt♠♣t

Page 129: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❯ ❳

t♥♠ ♦①

s st♦♥ ♣rs♥ts rsts ♦t♥ ♦♥ s s ♦♥ t tt♥♠ ♦① rrr s ♦ 2 ♥st ♦ str♦♥t♠ tt♥t s ♠♥② ♠♦tt ② t ♥ t♦♠t ♣♦ssts ♦ ♥ ♠♥② r♥t ♠ ♥r♦♥♠♥ts t ♠♥t♥♦♥♠♥t ♥trs t♦ ♣r♦st tr♠♥t♦♥ sss ♦ t②♣s ♦ s s♦♥ t 2 rrr r r♦♥ ♥ ♣r♣r t ♦♣t t♦r♣② t ♦2♥ ♦ ♥tr ②rs rs♣t②

♦22♦2

r ♦♦♠ t♠♣rtr ♠sr♠♥ts ♣r♦r♠ ♦♥ t♦2♥♠2♥♠♦2♥♠♥♠♥♠ s♠♣ ♦♥ tss② ①s

strtr ♦2♥♠2♥♠♦2♥♠♥♠ s r♦♥♥ t P ♠r ♦♥ sstrt ♥ ♣♣ t ♥♠ s♥♣♦st♦♥ ♦♥t♦♥s sr ♥ st♦♥ 2 ♣♦st♦♥ t♠♣rtr s♣t t sq♥t r♦♦♠t♠♣rtr ♠sr♠♥ts s♦ tt tst ①ts rs♦♥② ♥ ♥t♣r ♠♥t③t♦♥ stt rs♦♥ ♦r t ♣t s ♥♦t ♣rt② ♥ s t♥tt② ttrt t♦ 2 · 10−7 ♠r ♣rssr r♥ t ♦r ♦2 ♣♦st♦♥ t t t

Page 130: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❳

t♠♣rtr s♠r② t♦ t s ♦ s s sr ♥ t♦r♠r st♦♥

r ♠♣ ♦ ♦2♥♠2♥♠♦2♥♠♥♠s②st♠ ♥t♦♥s ♥② ♦r♥ ♥t♦♥s ♦t ♦ r s♦♥ t ♥ rtss ♦rrs♣♦♥ t♦ t t♦♣ ♥ ♦tt♦♠ ♣rts ♦ t s♠♣ rs♣t② ♦ tttr s tr ♥♥

st ♥r♥t t st♥r t♦r♣② ♥ tt♥ ♣r♦r tr rsst♥r ♣r♦ts r ♠sr s♥ t rss P ♣r♦r s♥ ♠❱ s ♥ t ♣♦♥t ♦♥tt ♠♦ ♣r♦t s r t♥ ts♠ ♦rr ♦ ♠♥t 105− 106µΩm2 ♥rs♦r♥ t tr ♦♠♦♥t②♦ t s rt② ♦ ♥♠r ♦ ♦r♥ ♥t♦♥s s ♦t♥♠♦♥ t s♠st ♦♥s t♦ µ♠ ♥ ♠tr t♦ t t t♦ ♣r♦ss♥ t ♦tr ♥ s♠ ♦r♥ ♥t♦♥s s♦ ♥s② ♣r♦t ttrsts r♦♠ t ♠t t♦r♣② rs♦t♦♥ ②♥ ♠♥s t r♦t sss sr ♥ st♦♥

s♠♣ s t♥ t ♥ ♦♥ ♦ t ♥t s s ssq♥t② ♥♥ t ♥ r ♦r ♥ ♦rr t♦ tr♠♥ t ♥♥♥ ♠♣t ♦♥ s②st♠♣r♦♣rts s s♦♥ ♦♥ t ♣♦st♥♥♥ ♥rs tr rsst♥s ② ♦rrs ♦ ♠♥t ♥ tr♥ ♥rs ② ♣ t♦ ♦♥ ♦rr ♠♦r ♦♦♥♦♥ t♦ t rsst♥ ♦ t ♥t♦♥s ♥rss st ♣♦♥ ♦♦♦♥ t♦

Page 131: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❯ ❳

r t ♥♥♥ ♥ ssq♥t ♦♦♦♥ ♠♣t ♦♥ t ♣r♦t ♦sr ♦2♥♠2♥♠♦2♥♠♥♠ ♥t♦♥s ♣r♦t ♥ t r♥ stt ♦ ♥t♦♥s ♥ tr ♥♥♥ t ♠srt r♦♦♠ t♠♣rtr r ♥ t r♥ t ♠♣rtr ♣♥♥ ♦ t②♣ ♥♥ ♥t♦♥ t 10µ♠ ♠tr ♠sr t ♠❱

tr t st③s ssts tr♠ tt♦♥ ♦ ♦♥t♥s♦ t s sr ♥ st♦♥

rrr ts ♦ s r tr♠♥ ② st②♥ tr rr♥t♦trtrsts t r♦♦♠ ♥ q ♠ t♠♣rtrs ♥ ♣♣②♥ t I ♠t♦♦r rsts r ♠♦♥ ♥t♦♥s ②♥ ♣♦♦r②♣r♦♥♦♥ s♣s ♦rrs♣♦♥♥ t♦ t ♥tr rrr ts r♥♥ t♥ ♥ ♠❱ rrs♣t t♦ tr t ♥ ♥♥ ♦r ♥♦t ♦♥② ♥♥ ♥t♦♥s s♦♥ ♦♥ t r I s♣s t s ♦ ♥rs r ♥♦t r♣♦rt♥ tr 2s ♥t♦♥s r t tr♦♥ rrr t s rtr st♠t t♦ ❱ ❬❪ ♥ t ♦tr ♥ t♦rt t♦♥s ♣rt t♣rs♥ ♦ ♦t ♦①②♥ ♥ tt♥♠ ♥s ♥ t r②sts t♥ ♥ ❱ ♦ t ♦♥t♥ ♥ ♠♥♠♠ ss♠♥ tt t rrr t♦ t♥ ♠ ♠② r ❬❪ t s♣s ♦sr ♠② rst r♦♠ ts♥s t s t♦ ♥♦t tt t ♦ r② ♣r♦♥♦♥ trs ♥ rsts♦ t I ♠t♦ s t②♣ ♦r ♥t♦♥s ②♥ ♦ s♥ ❬❪

♥t♦♥s r♦♠ t ♦22♦2 strtr s♦ ♥♦ t r♦♦♠ t♠♣rtr ♥ ♥ t ♥♦ s♥ ♥ t r♥ stt s ♦sr ♦rt ssq♥t srt♥ s st♦♥ t t ♦ t♠♣rtr ② ♥s

Page 132: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❳

r ♦r♠③ s♦t I ♠sr♠♥ts t♥ ♥ ♦♥ sr♥♥ ♦2♥♠2♥♠♦2♥♠♥♠ ♥t♦♥s t ♠trs ♦ 20µ♠ ♥ 30µ♠

♥ rsst♥s ♦♠♣♥ ② ♣♣r♥ ♦ t s♥ s rst s ♥♦tr♣r♦ ♥ ♦t t rsst stt ♥ t s♥ s♠ t♦ ♥♣♥♥t ♦ t ♣♣ s s♦s ♥ ①♠♣ ♦ tt tr s♦♥s ♦♥ s♥ t ♠❱ s♦ rsst♥ ♥rs ♦♠♣♥ ② t♣♣r♥ ♦ ♥t rs tr ssq♥t rt♥ t ts♠ ♥ s♥ ♦ s ts rsst♥ r♦♣♣ ♦♥ ♥ t ♠ ♣♦st rtr rt♥ t t s♠ r t♥ ♣♦st ss ♥ ts♦rr rst ♥ r♥♦♠ rsst♥ st♥ ♥ ♥♦ t s♥ s r②st♥s r♦♠ t ♥♦s ♦r s ♦sr ♦♥ s ♣r♦ssr♦♠ t s♠♣ ♦r t st ♠♥t♦rsst♥ s♥ ♠sr ♦♥ t♥♥ ♥t♦♥s s s♥♥t② ♦r ♣ t♦ ♥♦t s♦♥ t♥ t ♦♥♦sr r♦♠ tr ♥♦♥♥♥ ♦♥tr♣rts

♠r② t♦ t s ♦ r3s s t♦ t st ♦ ♦r ♥♦ ts♣r♠♥r② rst ♦♥sttts t ♦♥② ♥ ♦ rs♦♥② r r♦ss 2s ♥t♦♥s t tr♥st♦♥ ♠t tr♦s

♥ s ♦ ♦t ♥♦♥♥♥ ♥ ♥♥ s♠♣s ♦ t rrr tsr♦♠ ❱ ♥ ♦ ♦ts t tr♦♠rt♦♥ ♥ trr r♦♠

Page 133: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❯ ❳

r ♠sr ♦♥ s♥ ♥♦♥♥♥ ♦22♦2 ♥t♦♥t 20µ♠ ♥ ♠tr r♥ s♦ R = 14.7kΩ ♥ ♥♦s② rtrsts t ♥♦ s♥ ♥♦t s♦♥ srt♥ t ♦♥st②rs♥ s ♥ t ♦tt♦♠t♦t♦♣ rt♦♥ ♦ t tr♦♥s ♦ rst ♥ r♥♦♠rsst♥ ♥s t ♥♦ s♥ ♥t ♠❱ rt♥ ♥ t ♥t s ♦sr r sq♥t rt♥ t t s♠ ♠❱♦t ♦♥ ♥ ② r♥♦♠ rsst♥ ♠♣s ♥ ♥♦s② rtrsts♥♦t s♦♥ ♥t ♥①♣t ♣♦st r r rtr srt♥ ♥♦t rst ♥ ♥② r s♥

♠❱ sst tt ts 2 rrrs ①t ts r strtr② s♦rr ♠② ttrt t♦ t 2 ♣♦st♦♥ t♠♣rtr ♥s s②st♠s t s♦rr ♣②s r r♦ ♥ t s♣♥♣♦r③ tr♥s♣♦rt s ts ♥♦t strt ♦♠♦♥♦s② t rtr ♦s tr♦ ♦ t ♦♥rt♦♥s tt sr s ♦♥t♥ ♥♥s s②♠ t s♦s tt ts ♥♥sr rtr③ ② ♦ t ♣♦t♥t rrrs❬❪ s t s ♥ ♦r①♣r♠♥t s♠ t♦rs s♦ sr t ♣♥♥ ♦ t s♥ ♦♥t ♥rt ♣♦st♦♥ ♦ ♦♥t ♠♣rts rt② t♦ t r♠ ♥s ♦③ stt ♣♣rs t♥ t F ♥ F+eV r♥ t ♦♥trt♦♥ ♦tr♦♥s t♥♥♥ tr♦ t ♠② ♥rt t t♥♥ ♠♥t♦rsst♥ ❬❪ ss ♣♦ss ②♣♦tss ♥ t ♣r♦r♠ ①♣r♠♥t r t srt♥ trst ♦♣t♦♥ ♦ t stts t♦ ♥ ♥ ♥♦♥tr♦ ②

Page 134: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❳

♦2♦

r t ♥ ♦t rt ♣♥♥s ♦ t rt♦ ♥ tst ♦2♦ strtr

♥ t♦♥ tt♠♣t t♦ ♠♣r♦ t s♣♥♣♦r③ tr♥s♣♦rt r♦ss tr♥st♦♥♠t ♦①s s t♦ ♥tr♦ t♥ ♦t ②rs t 2 ♥trs ♥ ♦rr t♦ r t ♥tr ♦①t♦♥ s st♦♥ ♥ ♦ s♦ ♠ t♥tr sr t♦ ♥rst♥ ♥ tr♠s ♦ ts ♥ strtr ♥ t P ♠rt ♦2♦2♦ strtr s r♦♥♥t③t♦♥ rtrsts r ♦♥ t♦ s♠r t♦ ts ♦ t ♣r♦s②st ♦22♦2 s♠♣ ♦r s♣t t ♦rrt t♦r♣② ♣r♦ss♥ ♥ rt② r ♥♠r ♦ ♥t♦♥s s♦♥ ♦rrt s ♦t ♣r♦ts r②♥ t♥ 105Ωµm2 ♥ 106Ωµm2 s ♣r♦r♠ ♣♦♦r②r♦♠ s♣♥tr♦♥ st♥♣♦♥t r t♠♣rtr ♣♥♥ s s♦ s♠r t♦ tt♦ t ♦22♦2 ♥t♦♥s ♥ ♥♦♥ ♦ ♥t♦♥s s♦ t s♥ ♥ tr r♥ stt srt♥ t t♠♣rtr rst ♥ r♥♦♠ s♥ rrss t st ♦sr ♥ ♥ ♥♠♦s ♦♥ ♥♦♥♥♥ ♦ ♠tr 10µm2 ♥ ♥ s ♦t♥ ♥trt r♦♦♠ t♠♣rtr ♥♦r r♦♠ ♥♥ s ♥ t s ♣♦♦r ♣r♦r♠♥s r ttrt t♦ t s♠ rrr st♦rt♦♥s s ♥ t ♦22♦2s

Page 135: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❯ ❱ ❲

♦♥s♦♥s ♥ ♠♦ t♦rs

♥ t ♦♥st sts ♦ r3 ♥ 2s s tt♠♣t t♦ rs♦ sr sss ♥tr tr♠♥t♦♥ ♦ r3 r ♥ 2 ♠①♥ ts ♥t♦♥ ②r③t♦♥ t t ♥tr ♥ ♥tr ♦①t♦♥ t♦ ♦①t♦♥ ♥t♣② ♦ t ♠tr ♦ s ♦2 ss ♦r s ♦♦♥t♠♥♥ts ♥ t ♠r t t ♥ ♣rssr ttr ♦♥ rts trt s ♣rssr ♥ t ♠r ♦r t t♦♥ ♦♠♣♦♥♥ t tt t♦r tr♦ s ♥♥ ♦r t rrr ♣♦st♦♥ ♥ t♦ ♥ r♣rssr rst♥ r♦♠ ①ss ♦tss♥ t♦ t rt ①♣♦st♦♥ ♦ t P♠r r♥ t ♦♥ ♦ s♠♣s tr t s ♥♦t ♦t s♣t t♥r♠♥t ♠♣r♦♠♥ts ♥ t strtr ♦ s♠♣s ♣rs♥t t s sst ttt s♥ ♦ t ♠r ♣rs t st② ♦ s t ♦r tr♦ ♦♥sst♥ ♦ tr♥st♦♥ ♠t ♥ ♦t s t ♦♥sq♥ rsr s rtt♦rs 0.7r0.3♥3 ❯s ♦ s t ♦tt♦♠ tr♦ ♦ rst ♥♥♦ ♦①t♦♥ ♦ t ♦r ♥tr ♦r♦r t 2♦ strtr ♦♣rs♥t ♥♦ sss ♦♥♥t t♦ t ♥rt♥t② ♦ t rrr tr♠♥t♦♥

r ♦♦♠ t♠♣rtr t ♥ ❯ rt ♠sr♠♥ts ♦♥♥♠ strtr rt t t P st♣ ♥ ❩ ♥♦t♦♦ ♥ ③r♦ ♦♦ ❯ ♠sr♠♥ts rs♣t②

♠s r♦♥ ② t r♦♣ s♥ t P st♣ r stst♦r②r♦♠ t ♠♥t st♥♣♦♥t ② ①t ♦ ♦r rrs ♥ r t♠♣rtr ♦ ♦t ♦r♦r t ♦♦ ♥ ③r♦♦♦ s♣r♦♥t♥ q♥t♠ ♥trr♥ ❯ ♠sr♠♥ts ♥♦t s♦ ♥② r♥ ♠♥s tt t r②st s r ♦ ♠♣rts

♦r s ♦♥t♥♥ ♦r♥ tr♦ r r② t t♦ ♦t♥ ss♥t② t♦ ♦①②♥ ♦♥t♥t sss t♥ t ♥♦♠♥② r♦♥ ♠tr

Page 136: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❳

♥ t ♦①②♥♥② ♦ ♠s strs t ♦①♥ tr♦♥tr♥sr ♠♥s♠ rsts ♥ rst② r ♦♥t♥ ♦ t ♠tr♥ s rs t♦ ts ♥st♥ ♥tr ❬❪ s tr♦r ♠♣s tt t s rtt ts ♠s s♥t② ♦①②♥t r♥ t r♦t ♥ r♠♥ s♥t②♦①②♥t r♦♠ t r♦t st t♦ t ♠sr♠♥t st ♥ t P♠r t ♠r ♦ ♦①②♥ r♥ t r♦t ♣r♦ t♦ ♥♦t ♥♦♥ ♦rr t♦ ts st♦♦♠tr②

s t rst t②♣ rsst♥ ♦ t ♥♠ t ♦tt♦♠ tr♦rst♥ r♦♠ t st♥r t♦r♣② ♣r♦ss♥ s ♦ Ω ♦rr ❱st♦♥t♥ s♣♣rs ♣♦♥ ♦♦♦♥ r♥ ♠♦r t♥ Ω r② t ♦ t s ♥♠sr t♦ s♥s♥ ♣ts ♦ t st♣♦s② s rsst♥s ♥♦t ♦ ♥② st② ♦ s

r ①♣r♠♥ts r ♣r♦r♠ ♥ ♦rr t♦ tr♠♥ tr t sst♦♦♠tr② ♦ t ♠tr ♦ ♣r♥t t t rst st♣ ♥rs♥ t♦①②♥ ♦♥t♥t r♥ t ♣♦st♦♥ s tt♠♣t ❬❪ ♦r trsst t♥ s②st♠ s ♥ ♦rr t♦ ♠♥t♥ t sstrt t♠♣rtr t r♥ t r♦t ♦t ♦①③ ♥t② t♦ ts r♦♥ ♣♦♥♥♠r♦s tt♠♣ts

tr♦ t②♣♥♥♥ ♦rrt② t②

t♠ t ♦rt Ω Ω Ω Ω Ω Ω

♥♥ ♦ ♥t♠♦s♣r ♥♥♥ t♠ ♦ sst♦♦♠tr0.7r0.3♥3 ♦r tr♦s t

♥♦tr ② t♦ ♥ t ♣r♦♠ s t♦ ♣r♦r♠ ♥ t♦♥ ♥♥♥ ♦t ♦r tr♦ ♦♦♥ t s♦♥ t♦r♣② st♣ ♥♥♥ s ♦♥t ♥ r ♥ ♦rr t♦ r♦①②♥t t st② s ♣r♦r♠ ♦♥ t♦t②♣s ♦ s♠♣s t ♦rrt② st♦♣♣ ♥ t rrr ♦r st② ♦rtrr♥ t♦ t tr ♥ ♥♥♥ ♦t♥ rsst♥ s ♦rt ♦r tr♦ ♦ t♥ss ♥ s♣ tt r s♠r t♦ s r r♣♦rt t♦ ② ♦rrt rsts ❬❪ ♦r t ♦r tr♦ rsst♥r♠t② ♥rs ♦♥ t 2 ♥♣st♦♥ s ♣r♦r♠ s ♦ trrt ①♣♦sr ♦ t ②r t♦ t ♠ ♦r ♦①②♥ ♣♠♣♥ ♦ ② t sst♦♦♠tr 2 rst s ♦ ♠♣② tt s♥♦t ♠♥t♥♥ ts ♦①②♥ st♦♦♠tr② tr ♥♦♠♥② ♦t♥ tr♦ t♣♦st♦♥ ♦r tr♦ t ssq♥t ♥♥♥ ♥ r r♦t ♦♥t♦♥s ♦ ♦ t♥ rs♣♦♥s ♦r ts t♥♦♦ s♦rt♦♠♥ t ♣♦♦r

Page 137: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❯ ❱ ❲

♣r♦r♠♥ rsts r♦♠ t s♦♥ s ♠♦r st 2 ♦r ♥ t s♦♥♥tr 34 ♣sst♦♥ ②r ♠② ♥ ♦r s s

Page 138: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❳

Page 139: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♣tr

♥s♠ ♦①

s ♣tr srs sts ♣r♦r♠ ♦♥ s strtrs sts♥ ♥t♦ t♦ st♦♥s sts ♦♥ ♠♥s♠ ♦① ♠s rr♦♥ s♥ t ②r ②st♠ t♥ st tr② ♥ ♦♣t② r♦♠ trt st♥♣♦♥t st② ♦ s ♠♥t t♥♥ ♥t♦♥s s tttr st♦♥ srs t♦ r♥t ♣♣r♦s t♦ t♥♥♥ s t s s♦ s♣t♥ t♦ ♣r♠♥r② rsts ♦ t ♥st ♣r♦ss♥ ♦ s r♦♥ t t ②r ②st♠ ♥s sss♦♥ ♦♥ sss rt♥ t♦ t s♣ttr ♠r♣rssr ♥ st② ♦ ♦s strtrs r♦♥ ② ♥ t t ♥sttt♥ ♠♦r ♥ ♥②

rrr sts

s t s ② ♣t t rrr qt② s r ♠♣t ♦♥ t ♣r♦♣rts ❲t♥ t t♠r♠ ♦ ts tss ①t♥s sts r ♣r♦r♠♦♥ t ♠♥s♠ ♦① r♦t ♦♥t♦♥s tt str♦♥② t t qt② ♦ tstr

♣t tt②

s ♠♥t♦♥ ♥ st♦♥ ♦①②♥ ts ♣② ♥ ♠♣♦rt♥t r♦ ♥ t rrr♦r ♥ ♦rr t♦ tr t ♥st② ♦ t ts r♥ t ②r ②r②st♠ ♣♦st♦♥ ♦①②♥ s ♥tr♦ ♥ t♦♥ t♦ t r♦♥ ♦ rqr② ♠♥tr♦♥s t♦ ♠♥t♥ t ♣s♠ ♦r♥ ♣rssr r♠♥ ♥♥1 · 10−3 ♠r t ♦①②♥t♦r♦♥ rt♦ s r r♦♠ t♦ ♦rs♣ ♣♦st♦♥ r♥s

r ♥♠ s♠♣s t r♥tO2/Ar rt♦s r r♦♥② ♥r♥t ♦♣t tr♥s♠ss♦♥ s♣tr ♠sr♠♥ts s♥ t ❯❱❱sPr♥♠r ♠ s♣tr♦♣♦t♦♠tr tr tr ♦♣t s♦r♣t♦♥s t rsts r s♦♥ ♦♥

Page 140: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯ ❳

r ♣t s♦r♣t♦♥ s♣tr ♦ ♥♠ s♠♣s rt♥r t s♠ ♣rssr t t r♥t O2/Ar rt♦s strtrt trsr strt ❬❪

r r tr s♥♥t s♦r♣t♦♥ ♣s ♦r t s♠♣ r♦♥ ♥ t ♣rr♦♥ ♦♥t♦♥s ♣ ♣♦st♦♥s r ss♠ t♦ r♣rs♥t s♦r♣t♦♥s ♦♥ t♦ ♦①②♥ ♥② F2 ♦r ♥tr t ❱ ❬❪ ♥ t ♦①②♥ ♥tr ♥s♥② r ♥② F ♥ F+ ♥trs rs♣t② t ❱ ❬ ❪ ♣♦st♦♥ ♦ ts ts ♥ t ♥r② ♣ s s♠t② s♦♥♦♥ ♥ rtr♥ t♦ ts ♣tr sr t♠s tr♦♦t t ♥②ss♦r♦r ♣ tt ♥ ss♦t t ♦② r ♦①②♥ ♥②F 2+ ♥tr s s t ❱ ❬ ❪ t t ♥♦t ♣② s♥♥t r♦ ♥t ♥tr♣rtt♦♥ ♦ rsts t s ♥t tt ② ♥rs♥ t ♦①②♥ ♦♥t♥tr♥ t r♦t t s♣tr t ♦ ♣s rss s♣② tt ♦ t ♦♥ttrt t♦ t F ♥ F+ ♥trs t ❱ s♣♣rs ♥r② ♥tr②

tr ♠sr♠♥ts

♥ ♦rr t♦ tr♠♥ t ♠♣t ♦ ts ♦♥ t t♥♥♥ tr♥s♣♦rt ♦♥tt♦♠ ♦r ♠r♦s♦♣② s ♣r♦r♠ s♥ t rr ♥♦♦s ♥ ♦♦rt♦♥ t ❲ ♦ t ♦ t♦♥ ❯♥rst② ♦♥ ♥♠t ②rs r♦♥ t♦♣ ♥♠♥♠ sts ②rs r r♦♥♥ ♥ O2/Ar rt♦ s♥ st♥r ②r ②st♠ ♦♥t♦♥s ♥ t ttrs t rst ♠♦♥♦②r s s♣ttr t♦t ♦①②♥ ♥tr♦ ♥ t

Page 141: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

r ♠t r♣rs♥tt♦♥ ♦ ♦①②♥ t s ♥ t rrrt ♥ ♣ s ss♠ t♦ ❱ ♥ F t♦ ♥ t ♥tr ♦ t rrr♠rs ♥♦t s♦t ♥r② r♥s ♥ ❱ t♥ t F♥ t ♦t ♦rrs♣♦♥♥ t st ♦ rr♦s ♣t ♦♣t s♦r♣t♦♥ ♥ ♠ss♦♥♣r♦sss ss♦t t ♦rrs♣♦♥♥ t sts tr s ♦♥tr♣rts♠r ♣♦♥♦♥ssst r①t♦♥ r♦♠ ①t stt t♦ r♦♥ stt ts r ♥♦t r♣rs♥t ♦r rt②

♠r ♥ ♦rr t♦ ♦ t r♦♥ ♦① ♦r♠t♦♥ t t ♥trs♣t t t tt t r♦♦t ♠♥ sqr r♦♥ss r♠♥s ♠♦st② ♥♥

tr♦♦t t st② t ♥st② ♥ ♥t♥st② ♦ t ♦ rr♥t ♦ts♣♦ts sr② ♦♥ s ts ♦ rr♥t ♥♦♠♦♥t② s ♥♦t t♦♣♦r♣②rt t s t♦ rst r♦♠ t ♥st♦r rrr t♥ss ♦r ts t t♦♥sr♥ t ♣♦t♦♠♥s♥♥rr rs ♥ t ♦①②♥ ♥② ♥st②t ♥rs♥ ♦①②♥ ♦♥t♥t ♥ t r ♣s♠ ss♠ tt ts ♦ rr♥t♠♦t♦♥s r ss♦t t ♦①②♥ ♥s ❬❪ tt♥ ♦ t t rs t r rr♥ts ♦ ♣ ♥ ♣ ♦r t ♥ 2

rrrs rs♣t② ♠♣s t t qtt s♥♥t ♠♣r♦♠♥t♥ t rrr t

s ♦♥t ♦ts♣♦ts ♦♥ t ♦ t♥♥♥ ♠♣s ♦r♥t r♦♠ ts ♥t rrr rr♥t♦t ♠sr♠♥ts r ♣r♦r♠ t ♥ ② r♦♠ t

Page 142: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯ ❳

r ♦♣♦r♣ ♠♣ ♦ t rrr ♣♦st t♦t ♦①②♥ ♣rs♥t♥ t ♠r r♥ t r♦t rst s s♠r t♦ tt ♦r t 2 ②r ♦ t♥♥♥ ♠♣ t ❱ s ♦ t 2 ②r ♠ ♦r t 2

②r ♦♠♣rs♦♥ ♦ t♦♣♦r♣ strt♦♥ t♦♥ r♦♠ t ♥♦♠♥t♥ss ♦r ♦t s♠♣s ♦ rr♥t strt♦♥ ♦♠♣rs♦♥ r♦♠ rs ♥ ❬❪

♦ts♣♦ts ♥ ♦rr t♦ st② tr ♠♣t ♦♥ t rrr t s s ♦♥ ♦♥♦t s♠♣s s♥ t ♦r♠♥t♦♥ ♦♥t♥ ②♣ ♥ r♣r♦❱ rs r s♦♥ ♦♥ ❲ ss♠ r tt t tr♥♦♥ ♦ t ❱ rr♣rs♥ts qtt st♠t ♦ t t rrr t ❬❪ ♥ ♦rr t♦tt ♥ ♥rst♥♥ ♦ t ❱ r t s♠t s r♥ ♥ st rst ♠♦♥♦②r ♦ t rrr s ♣♦st t♦t ♥② ♦①②♥ t♥t ♠r t ♦r ♥tr ♦ t 2 s♠♣ ♠② rs♠ t ♦♥ ♦ t

Page 143: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

r ❱ rtrsts ♠sr t ② ♦♥t t♣ ♦♥ ♥ 2 s♠♣s ♦t t ♥ ② r♦♠ t ♦ t♥♥♥ ♦ts♣♦ts ❬❪

s♠♣ r♦♥ ♥ t ♣r r♦♥ s t s t ♦r ♥tr s ♣r♦ tt ♥t s t♥ rs ♠sr ♥ t r♦♥ ♦♦ ♦r ♦ts♠♣s ❲t♥ t ♣♦st ♦t r♥ ♦♥ r♦♠ t♦ 2 trrr t rss r♦♠ ❱ ♣ t♦ ❱ ♥ t r♦♥ ♥ r♦♠ ❱ t♦❱ ♦♥ ♦ts♣♦ts 2 r♦♥ ♥ 2 ♦ts♣♦t rtrsts rs♠r ssts tt t ♥rs ♥ ♦①②♥ ♦♥t♥t r♥ t r♦t rsts♥ t s♣♣r♥ ♦ t ts ♥ t♦ t ❱ rrr t ♦r♦rt t♥ ❱ rrr ♣rs♥t ♥ t r♦♥ ♦ t 2 s♠♣①st ♦♥② ♦② ♦♥ ♦ts♣♦ts t♥ t ♦♥ t♦ t ♠♣r♦♠♥t ♦t rrr strtr ss♠ tt t r♠ s ♥ t ♠ ♦ t ♥ ♣ ❬❪ ♠② ttrt t rrr t ♦ ❱ t♦ rstr♦♠ t ♣rs♥ ♦ t sts ♦ t F2 t②♣ r rrr t ♦r♦♥ ❱ ♦rrs♣♦♥s t♦ F ♥ F+♥trs tr♥♦♥ t r♦♥ ❱ ♥ tr♦♥ ♦ t s♠♣ s ss♠ t♦ t ♥tr♥s rrr t ♦ t ♥st♦r

♦♠♥♥ rsts ♦ ❱ rtrsts t ts ♦ t s♦r♣t♦♥ s♣tr ♦♥♠② s tt F ♥ F+ ♥trs ❱ ♦ t ♦♥t♦♥ ♥ ♥ rrs♣♦♥s ♦r t ♦♣t s♦r♣t♦♥ t ❱ ♥ t t rrr tt r♦♥ ❱ r ♠♦st t♦t s♣♣r♥ r♦♠ t s♦r♣t♦♥s♣tr ♦ t 2 s♠♣ s ♦♦ ② t s♥♥t ♥rs ♦ t rrrt ♥ t r♦♥ r♦♠ r♦♥ ❱ t♦ ♣ t♦ ❱ s ssts tt F ♥

Page 144: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯ ❳

r ♠t r♣rs♥tt♦♥ ♦ t rt♥ ♣rt ♦ t ♦r③♦♥t s ♦rrs♣♦♥s t♦ ②♣♦tt tr ♠sr♠♥t ♥♦♥tr♥ s♥ ♦ts♣♦t rt s s♦s t②♣ ♦t ♦ t ♦♥t♥tt♦♥ ② ♦♥t ♦ts♣♦ts ♦ t s♠♣ r ♠♥t ♥ t s♠♣ ❱ ♦ r♦♥ ♦♥t♥ ♦ t s♠♣ s r♣♦rt ♦♥ t s♠♣ ♦ts♣♦ts r♦♥ ♦♥t♥ ♦ t s s♥♥t② ♦r t♥ ♥t s

F+ ♥trs ♣rs♥t tr♠♥ t t rrr t r♦♥ ❱ ♥ rt②r t tr qt② ♦ rrr

♦♠♥♥ rsts ♦ ❱ rtrsts t t♦s ♦ t s♦r♣t♦♥ s♣tr ♦♥♠② s tt F ♥ F+ ♥trs ❱ ♦ t ♦♥t♦♥ ♥ ♥ rrs♣♦♥s ♦r t ♦♣t s♦r♣t♦♥ t ❱ ♥ t t rrr tt r♦♥ ❱ r ♠♦st t♦t s♣♣r♥ r♦♠ t s♦r♣t♦♥s♣tr ♦ t 2 s♠♣ s ♦♦ ② t s♥♥t ♥rs ♦ t rrrt ♥ t r♦♥ r♦♠ r♦♥ ❱ t♦ ♣ t♦ ❱ s ssts tt F ♥F+ ♥trs ♣rs♥t tr♠♥ t t rrr t r♦♥ ❱ ♥ rt②r t tr qt② ♦ rrr

♥ ♦♥s♦♥ ♦r ①♣r♠♥ts s♦ tt t ♥st② ♦ ♦①②♥ ♥s ♥ ♦♥tr♦ r♥ t r♦t ② tr♥ t ♦①②♥ ♦♥t♥t r♥ t ♣♦st♦♥ ♥ tt t ♣rs♥ ♦ rt♥ t②♣s ♦ ts ts ♥ t♦ rt♥①t♥t s♣♣rss s rsts ♥ s♥♥t ♠♣r♦♠♥t ♦ t rrr t♥ rt♦♥ ♦ ♣♦ss ♥sr ♦ts♣♦tr♥ ♠♥tr② rr♥t ♥♥s

Page 145: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

s st♦♥ sr rsts ♦t♥ ♦♥ s rt t t s♦♠st♥q sts ♦♥r♥♥ t s♣♥♣♦r③ tr♥s♣♦rt r rtr ♣r♠♥r②s ♠♦st ♦ t rt ♦r ♦♥♥trt ♦♥ t r♦t ♦♣t♠③t♦♥

s♥♥t ♣rt ♦ ts tss ♦♥♥trt ♦♥ rt♦♥ ♦ s s s♥ t ②r ②st♠s s♣ttr♥ ♠r t t s♦♠s ♣♦st♦♥st♦♥ t♦ t♥ s♣ts t s ♥♦t ♣♦ss t♦ r♦tt t s♠♣ r♥ t ♣♦st♦♥ ♠♥t♥♥ ♣rs ♣♦st♦♥♥ s♦ s t♦ ♣r♦r♠t ♦rrt ♥♠♥t ♦ t t♥♦♦ st♣ Pr♦♦♠tr ♥ tsts♣r♦r♠ ♦♥ s♠♣s r♦♥ ♥ t s♥ ♦ t r♦tt♦♥ s♦ t♦♣♦r♣ ♥♦r♠t② ♦ s♠♣s ❨t t rsst♥ s ♥♦t ♥♦r♠ r♦ss ♥ s♠♣♥ s ♦ t s♠♣ ♣rs♥t ♦♥ r µm2 rsst♥s ♦ ♥t♦♥sr Ω Ω Ω ♥ Ω ♥ tt ♦rr s s ♦rrs♣♦♥ t♦ ♣r♦ts ♥ µΩ♠2 ♥ rs♣t② r s♦s t ♦srrsst♥s ♦♥ ♦rt♠ s s ♥t♦♥ ♦ t ♥② s♣ ♥t♦♥ ♣♦st♦♥ r ♥t♦♥s s♦ ①♣♦♥♥t ♣♥♥ ♦ rsst♥ ♦♥ t ♥t♦♥♣♦st♦♥ ssts ♥r t♥ss rs ♠♦♥ t♠ ♥ ♦ t s♥trs ♦ t♥♥♥ r♠ ♥ t ♦r♠ ♦ ♥♦♥♥r rr♥t♦t rtrsts❬❪ s ♦sr ♦♥ ♦r ♥t♦♥s s ♥tr rrr ts t s♥ r♥♠♥s ♦r♠ r ❱ ♥ ❱ ♦r t ♦tt♦♠ ♥ tt♦♣ ♥tr rs♣t② r♥ ♦ rt ♦①t♦♥ sss t t ♦r♥tr

r ♣♦♥t rsst♥s ♦ µm2 ♥♠♥♠ ♥t♦♥sr♦♥ ♥ s♥ t s♥ t s♦♠s t♥q

Page 146: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯ ❳

r rr♥t♦t ♠sr♠♥t ♣r♦r♠ ♦♥ µm2

♥t♦♥ r♦♥ ♥ s♥ t s♥ t s♦♠st♥q ♣♦♥t ♥t♦♥ rsst♥ t ♠❱ s Ω

♦♠♣r ♣r♦ts ♦ ♦r ♥t♦♥s t t ♦♥s r♣♦rt ♦♥ s♠♣s ♥ t trtr ♠② s tt t♥ ts r♥ t s♥ ♦ ♠♦r t♥ s ♦sr ♦r ♥♦ s♥ s ♦sr ♦♥♠♥t t♥♥ ♥t♦♥s r♦♥ t ♦r ②r s♣ttr♥ s②st♠ ♥ t ♦t♠♣rtrs

t♦ s♥♥t rsts ♦♥r♥♥ t t ♥♥ ♦♥ ♣r♦♣rts ♦ t r②st r ♦t♥ s r♦♥ t t ②r ②st♠s s♣ttr♥ r♥♦t stst♦r② r♦♠ t s♣♥tr♦♥ st♥♣♦♥t s ♠♥t♦♥ t♥ t st♦♥ t r ss rt t♦ t ♣♦♦r s♣♥tr♦♥ ♣r♦r♠♥ ♦ t srt t t ②r s②st♠ s ss♠ t♦ t ①ss ♣rssr r♥♥♥♥ ♦ t ♦r tr♦

tr ♠♦♥t ♦r♥② t♥ t s♣ttr♥ ♠r s r♠♦♦①♥t t t♥ ♠♥ts ♦r ♥ 23 ♦ t♦ r t ♥♥♥ s ♣r♦r♠ ♥ ♦①②♥ ♦r t♦ ①ss ♦tss♥ ♦r ♥ ♠♥ts t s r♣ t ♣t♥♠ r♦ tr ♦r ♥ ♥ts s t st♥ss st ♦r s ♦tss♥ ♦ r♦♠♠ rst♥ ♣rssrs ♦ 10−6 ♠r r♥ t r♥ t t♠ ♦ rt♥ t rr♥ts♦t♦♥ ♦r t ♥♥♥ ♣rssr s t tr ♠♣r♦ t ♥♥♥♣rssr ♦♥ t♦ 10−7 ♠r t t t ♥ s ♦♥② ♦ ♠r ❯♥♦rt♥t② ♥②ss ♦ t rsts ssts tt ts ♣rssr r♠♥s ♥♦♠♣tt ♦①t♦♥r ♥trs

Page 147: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♦♦

s tss s t♥ ♣ t ②r s②st♠ s ♥ ♦♥st♥t② ♦♣♥ ♠♣r♦ ❲t♥ t t♠r♠ ♦ ts ♠♥sr♣t ♣t♦♥ r♥t ♣r ♦ t st♣ ♥ t ♦r♠ ♦ tt♥♠ s♠t♦♥ ♠♦t♦♥ s ♥r②♣r♦♠s♥ s♥♥t② ♦r ♣rssr r♥ t s♠♣ ♥♥♥ ♦r t s♦t♦♥ ♣r♦s ♥sss s ♦♠tt♥ t ♦r tr♦ ♥♥♥ st♣s ♦♥sr ♥ s ♠♦ ♦ rst ♥ ❱♦♠r❲r s♥ r♦tt s ♣♦ss tt ♠♦♥ t♦ ♦ tr♦s ♠② rqr

♦♦

s st♦♥ ♥♦♠♣sss rsts ♦t♥ ♦♥ ♦s strtrs r♦♥ ② ♥ r♦♠ t ♥sttt ♥ ♠♦r ♥ ♥② r tr ♣r♦ss♥ t P ts rt t♦ ts s s r ♣r♦r♠ t♦rs t♥ ♦ t tss ❲ sr ♦r ♣rs♥t ♥rst♥♥ ♦ ♦r rsts ♥ ♥ttr rt♦♥s ♠♣ ② ts rsts

♥♠♦♥♠r♥♥♠♦♥♠♥♠♦♥♠strtrs r r♦♥ ♦♥ ♠♦r♣♦s ♦r♥♥ ss s♥ r♦t ♦♥t♦♥ssr ♥ st♦♥ s ♠♥s tt ♦♥ ♦ tr tr♦s s ♠♥t②♣♥♥ ♥ t rt♦♥ ♦♦♥ t ♠♥t③t♦♥ rt♦♥ ♦ t ♥trr♦♠♥t strtrs r ♣♣ t ♥♠Pt♥♠ ②r ♠r strtrst t♦t t t♦♣ ♦Pt tr②r r s♦ r♦♥ ♥ ♦rr t♦ st② t♥♠ ②r ♦♣t② ♦ ♦ t st② s t♦ tr♠♥ t ♠♣t♦ ♥♥♥ t ♦♥ tr ♠♥t♦rsst ♥ ♦♣t ♣r♦♣rts ♦rs ♦t s♠♣ t②♣s r ♥♦t ♣♦st ♥ t s♠ t t s♣rt② t s♣♦ss tt ♦srt♦♥s ♦ ♦r ①♣r♠♥t ♠② ♥♦t ♥♠♦s② ①♣♥s t♦ ♥♥♥ ♥t t♥♥ ♥t♦♥s r ♣ttr♥ s♥ t st♥r♦♣t t♦r♣② ♥ r t rst t♦ st t t rt st♣ tr tt♦♠t③t♦♥ ♦ ♠sr♠♥ts

♥r ♣r♦♣rts

P♦t♦♠♥s♥ ①♣r♠♥ts ♣r♦r♠ t ♥♠ ♥ ♥♠ ♥t sr♦♥ strtr tr♠♥t t t ♥♠ ②r ♥♦♠♣ss♥ t ♦rtr♦ ♥ t♥♥ rrr t ♥♦t t t♦♣ tr♦ st s♦ ♣s t ♥♠❱ ♥♠ ❱ ♥ ♥♠ ❱ tr ♦♥♦t♦♥ t♦t ♣♦t♦♥ ♥r② s ♥ ♦r ①♣r♠♥t s ♥♦t s♥t t♦ ①t F ♥ F+

♥trs s♦ t ♠♥s♥ rst♥ r♦♠ ts sts ♥♥♦t ♦sr rt② ttrt t ♣ t ♥♠ t♦ t rrs ♦♥③t♦♥ ♦ F ♥ F+ ♥trs ♥r♦♠♥t♦♥ ♦ tr♦♥s t♦ t t♦♣ ♦ t ♥ ♥ ♦tr t♦ ♣s♥♠ ♥ ♥♠ ttrt t♦ ♣♦t♦♥ ♠ss♦♥ ss♦t t r①t♦♥ ♦F ∗ ♥ F+∗ ♥trs t♦ tr rs♣t r♦♥ stts ♠r rsts ♥♦t s♦♥

Page 148: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯ ❳

r t ②♣ r♦♦♠t♠♣rtr ♣♦t♦♠♥s♥ s♣tr r♦♠ ♥ ♥♥ ♦r♥♦ st r♦♥ ♦♥ ♦r♥♥ ss ♥ ♥♥ ♦r t r ♦t tr t ♥♠ sr ①tt♦♥P♦st♦♥ ♦ t ♠♥ ♣ tr ♦♥♦t♦♥ s ♥♠ P♦st♦♥s ♦ t ♠♥♦r ♣sr ♥♠ ♥ ❱ ♠r rsts r ♦t♥ r♦♠ ♥♦♥♥♥ s ♥tr ♥♠ t ①tt♦♥ ♥♦t s♦♥ t ♠t r♣rs♥tt♦♥ ♦ t♦sr ♠♥s♥

r ♦t♥ ♦r t ♥♥ s s s ♣♦♥ ♥♠ t ①tt♦♥r♦r ♦♥r♠ ♣rs♥ ♦ t ♠♥t♦♥ t sts ♥ t rrrs st

❲♥ t♥ ♥t♦ ♦♥t ♣r♦ss♥ sss ♦ t sts s st♦♥ ♠♥t t♥♥ ♥t♦♥s r rtr③ ② r② ♥♦r♠ ♣r♦ts ♣rs♠♣ ♥ t ♣rtr s ♣rs♥t ♣r♦ts ♦ ♥♥ sr s♥♥t② ♦r t♥ tr ♥♦♥♥♥ ♦♥tr♣rts ♦r sts ♣r♦r♠ ♦♥ ♥♠r ♦ s♠♣s s♦ tt t r♥ ♥ ♣r♦ts ♦s ♥♦trst r♦♠ t ♥♥♥ ♣r♦ss t rtr r♦♠ st rt♦♥ ♥ t s♠♣ r♦t ♦♥t♦♥s ♦r ♣r♦ss♥ sss s♣② r♦♠ t rrr ♦rt♥r♥ t st♣ ♦ t ♣♦t♦t♦r♣② s st♦♥ ♦r ts

r ♥t♦♥s ♦ t②♣ r st ♥ ♦rr t♦ ♣r♦r♠ t ♠sr♠♥ts ♥ s♦ r♣r♦ rtrsts ♥ r ♣♦t t②♣Iabs r♣ ♦r ♦t ♥ ♥♥ ♥ ♥ ♥♦♥♥♥ s ♠t♦ ♠♦♥

Page 149: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♦♦

r sst♥r ♣r♦ts ♦ ♥♥ ♥ ♥♦♥♥♥♦♦ s♠♣s t ♦r s♦rt ♥ ♦♣♥rt s r s♦♥ s ③r♦

♦trs ♠♥t♦♥ ♥ st♦♥ s sts s t♦♦ t♦ ①trt t trrr t ♦ ♠♥t t♥♥ ♥t♦♥ ♥ s ♦ t ♥♦♥♥♥ t t rrr t s ❱ ♦r ♦t P ♥ P ♦♥rt♦♥s ❲ ♥♦ttt ♥♥ t s♠ ♦r ♦t P ♥ P ♦♥rt♦♥s s ♥ t ①♣t♦r ♣r♠♥t rrr ❬❪ ♦r t rrr t ♦ t ♥♥ s♦s ❱ ♥ t P s ♥ ♠♦r t♥ ❱ ♥ t P s rtr♠♦r tsrrr t s ♦♦s② ♦r t♥ tt ①♣t ≈❱ t rt ♥♦r ♦♥t♦♥ ♥ t s tr♦r ttrt t♦ ts ♥ tr♥ ts sststt ts ts ♥ ♠♣t ♦♥ t s♣♥ ♥♦r s②♠♠tr②♣♦r③ tr♥s♣♦rt♥ t s②st♠ s s rtr

♥t③t♦♥ rs ♦ ♦t s♠♣s ♠sr t r♦♦♠ t♠♣rtr t t

♦♦♠ t♠♣rtr ♠sr♠♥ts ♥ ♦t r t♥ ❱ r ♥♦t ♣r♦r♠ t♦t ①♣r♠♥t ♣r♦t♦♦ tt s ♠♣♠♥t ♥ ♦rr t♦ ♠tt t rs ♦ t trr♦♥ ♦r ♥ t r♥ t Iabs ♣ ♦rr t ❱ s t ♦♦♥♥②ss s♦ t ♣ s ①♣t t♦ t♥ ❱❱ r♥

Page 150: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯ ❳

r Iabsolute rs ♦r ♥ ♥♥ t♦♣ ♥ ♥♦♥♥♥ ♦tt♦♠ ♥ t P ♥ P r rt ♠♥t③t♦♥ stt ♠sr t♥ ♥ ♠tr ♦ ♥t♦♥s s µ♠ ♥ µ♠ rs♣t②

❯ st♣ r s♦♥ ♦♥ rs ♥ ♥♦♥♥♥ s♠♣s♦s ♥♦t t ♥♦t ♣rt② ♥ ♣ ♦ t ♠♥t③t♦♥ t t♣♣ ts ♥♥ ♦♥tr♣rt ①ts ♥ ♠♣r♦ P ♥♠♥t t♥st♦ t ♣♥♥♥ ♣r♦ ② t r♥♦ ♦r tr♦ ①♥ s ♥② ♥♥♥ ♥t③t♦♥ ♣♣♥ ♦ s♣ ②rs ♦ t ♥♥ s♠♣ s♠r ♦♥ t r♣ ♦r rt♦♥

Page 151: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♦♦

r ♦♦♠ t♠♣rtr ❯ ♠♥t③t♦♥ ♥ rsst♥ s ♣♣ ♠sr♠♥ts ♦♥ t ♥♥♦r♥♦♦ s♠♣ rr♦s ♥♦trt ♠♥t③t♦♥ ♦ tr♦s ♣♣♥ ♦ s♣ ②rs s s♦♥

❲ ♥♦ ♣rs♥t ♠♥t♦tr♥s♣♦rt rsts ❲ ♠♣s③ tt ts rsts rsttst② r♥t s t② r r♣rs♥tt ♦ s ♠sr ♦♥ t ♥♥st ♥ s ♠sr ♦♥ t ♥♦♥♥♥ st

t r♦♦♠ t♠♣rtr ♥♦♥♥♥ ♥ ♥♥ s s♦ ♥ s♥ rs♣t② rs ♥ s♦ t rs ♦ ♦t t②♣s ♣♦tt t rs♣t t♦ tr ♠♥t③t♦♥ rtrsts t s ♥♦tsr tr t ♦ ♦ t ♥♦♥♥♥ s s t♦ t P stt♥ ♥♦t ② ♦r ♥♦t ♥ ♦rr t♦ t ♥♥♥ ♦ ♥♦♥♥♥♥t♦♥s t ♦♥st② ♥ s ♣r♦♣♦s ♥ ♦rr t♦ s♣rtt rr②st③t♦♥ ♥ t P stt ♦r♠t♦♥ ①♣♥t♦♥s ♦r t ♦ ♦sr r♦♠ t ♥♦♥♥♥ s♠♣ r r♥ ♠② s♦ rst r♦♠ tt①tr③t♦♥ ♣r♦ss tt ts ♣ r♥ t ♥♥♥ ♥ t r②st♥t②♦ t rrr s ♠♣r♦ ♥ t tt ♠♣r♥t♥ ♦ ♦♥t♦ ♦ ts♣ rst♥ ♥ s♥♥t ♥♥♠♥t ♦ t s②♠♠tr② tr♥ r♦♠ s♣♥tr♦♥ st♥♣♦♥t s ♠♣r♦♠♥t s ♠ ♠♦r ♠♣♦rt♥t ♦♥sq♥s t♥

Page 152: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯ ❳

r ♦♦♠ t♠♣rtr ❯ ♠♥t③t♦♥ ♥ rsst♥ s ♣♣ rs ♦ t ♥♦♥♥♥♦r♥♦♦ s♠♣

t ♠tr s♦♥ ♦r t ♦r♠t♦♥ r♥ t ♥♥♥♥ ♦rr t♦ rtr ♥rst♥ t ♠♣t ♦ ♥♥♥♥ ts ♦♥ ♠

♥t♦tr♥s♣♦rt r t ♣r♠tr ♦ t♠♣rtr rr♥ t♦ t rsst♥ ♣♥♥ ♦♥ t♠♣rtr ♦ ♥ ♥♥ ♠sr t ♠❱s♦s st ♥rs r♦♠ Ω t♦ Ω ♥ t ♣r stt ♥ rt② ststrt♦♥ t ♥ t ♦tr ♥ t rsst♥ ♥ t ♥t♣r s ♣s♥rs♥ ♣♦♥ ♦♦♦♥ r♦♠ Ω t♦ Ω ♥t t t♠♣rtr rs r♦♥ ♦r ♥ qtt② ♥rst♦♦ ♦♥ ♦♦s t t ♥ strtr♦ ♦ tr♦s P s ♦r ♦ rt r ♥t♦♥ ♦ t♠t ♠①♥ ♦ s②♠♠tr②♣♦r③ tr♥s♣♦rt ♥♥s ♦ tr♦♥s ♦ t ♥t② ∆1↑ s②♠♠tr② t♦ t♥♥ ♥t♦ ∆2′,5↓ stts ♥ t ♦♥trtr♦ s♥r♦ s ♣r♦t ♥ s♥ ♦ t ♠①♥ s ♥t ♦tr ♥ t P s t♥♥♥ ♦ tr♦♥s t t ∆1 s②♠♠tr② s ②s

s ♣ t♦ ♦r st ♥♦ t♦♥s ♦ t ♦ ♥ strtr ♥♦t ♥ ♣r♦r♠ r ♥r② s ♦ rs♣t ♥s ♦ ♥ ♦ ♦0.40.40.2 ♦♠♣♦st♦♥t t ♥♥ ♦ ♦r♦♥ ♥t s ♦r ♥②ss s♦ ts r st ss♠♣t♦♥ ②s♦r♥t rsts

Page 153: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♦♦

r ♠♣rtr ♣♥♥ ♦ rsst♥s ♥ ♣r ♥ ♥t♣rstt ♦ t ♥♥ r ♥ t rs♣t② ♦ t s ♥t♦♥ ♦ t♠♣rtr ❱rt ♥s ♠r t♠♣rtrs t t t♠♣rtr ♣♥♥ ♦ t rt♦ ♥s ts ♦r ♠sr♠♥t s♣r♦r♠ t ♠❱

♦ rsts ♥ t rt② q strt♦♥ ♦ t rsst♥ ♥ t ♣r ♦♥rt♦♥ r♦♥♥ ♦ P ♥ P rsst♥s ♦♦s② s t♦ s♥♥t ♥rs ♥ t

t♠♣rtr ♣♥♥ ♦ ♥♦♥♥♥ s ♣rs♥t ♥ r s♣ ♠sr♠♥t s♦♥ s ♣r♦r♠ ♥ t ♣♦♥t ♦♥tt ♠♦ t ts♦s s♠ ♣r♦♣rts s ts ♦ t ♣♦♥t t②♣ t♦ ♠ ♦r rsst♥ ♦♦♥tts t♥ t ♦♥ ♦ t ♥t♦♥ Ω ♥ Ω ♦r ♦tt♦♠ ♥ t♦♣ tr♦srs♣t② s st♦♥ ♦t② ♦♠♣r t♦ ♥♥ s tr s ♥♦rsst♥ strt♦♥ t♥ t ♠sr t♠♣rtr r♥ ❲ r tt tsrts ♦ t tr♥s♣♦rt r♦ss t ♥♦♥♥♥ rrr ♦rs r♦ss t sts♥ t ♦ s ♦ t♠♣rtr

Page 154: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯ ❳

r ♥ ♥♠♥t ♥ s♠t ♦ tr♦s ♥♦♦ s②st♠ ♥ P↑−↑ t P↓−↓ ♥tr ♥ P↑−↓ rt♦♥t♥ ♥♥s s♠ts r r♥ ♦r tr♦♥s ♦♥ r♦♠ tt♦ rt ♦r ♦s ♦♥ t ♦♣♣♦st ② ttrs r q rr♥st♦ rs♣t trs sss ♥ t t①t ♦♥ t ♥t♦♥s tr t②♦♥t ♦r ♠①♠ ♦r ♠♥♠ t t I s♣tr P↓−↑ ♥♥ ♥♦t s♦♥ st ♠rr♦r ♠ ♦ t P↑−↓ ♦♥ t♦ t ♦s ♥♦t ♣r♦ ♥② rr♥t ♦①♣t t♠t s t①t

♥②ss ♦ t ❱ ♣r♠tr s♣

♦r ♥rst♥♥ ts r♥ tr♥s♣♦rt t♥ ♥♥ ♥ ♥♦♥♥♥s♠♣s ①♣♦r s♣♥♣♦r③ tr♥s♣♦rt t♥ t ❱ ♣r♠trs♣ ♥ ♥r tr♠s t♠♣rtr♣♥♥t ❱ rtrsts s♦ r②♦♦ r♣r♦t② ♠♦♥ ♥t♦♥s ♥ t s♥ ♦ t♦ tr♠♥rrr ts s♥ t I ♠t♦ tr r♦♥ ♦rr r♦♥ ❱ t ♥ t r♦♥ s trs♦ rs t ♥rs♥ t♠♣rtr s♠♣ ♣rt♦♥r② ♠sr♠♥t ♣r♦t♦♦ s ♠♦st ♦ t t♠♣rtrs ♠sr♠♥ts r ♣r♦r♠ t♥ ❱ t♦ ❱ ♣♥♥ ♦♥ t s♣♥t♦♥ ♦r ♥t♦♥ t②♣ ♥♥ ♥ ♥♦♥♥♥ sr s rst s♦♥ r♣r♦ Irel rtrsts

Page 155: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♦♦

r ♠♣rtr ♣♥♥ ♦ rsst♥s ♥ t ♣r ♥ ♥t♣r♠♥t③t♦♥ stt ♦ t ♥♦♥♥♥ r ♥ t rs♣t② ♦ t s ♥t♦♥ ♦ t♠♣rtr ♠sr♠♥t s ♣r♦r♠t ♠❱ ♥ t ♣♦♥t ♦♥tt ♠♦

♥ ❱ s♣

♥ r ♣♦t ♣♥♥ s t♠♣rtr ♥ ♣♣ s ♦r ♦t♥♥ ♥ ♥♦♥♥♥ ❨♦ ♥ t ♦♦rs r♦② ♦rrs♣♦♥t♦ ♥ r♦♣ r♦♠ t ♥t rs♣t② t s r② s tt t rt♦ rss ♠ str ♥ t s ♦ t ♥♦♥♥♥ s♠♣ ♦♠♣rt♦ ts ♥♥ ♦♥tr♣rt s ♥t♦♥ ♦ ♦t t♠♣rtr ♥ t ♣♣ ss r♥ s ①♣t s t tr♥s♣♦rt r♦ss t rrr s ♠♦r ♥♦r♥t ♥t ♥♦♥♥♥ s♠♣ ♦r♦r t rst ssts tt t♥♥♥ t

Page 156: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯ ❳

r ❱ ♦ t ♥♥ t♦♣ ♥ ♥♦♥♥♥ ♦tt♦♠♦♦ ♠♣rtr ♥ ♦t s♣♥ s ♥ ♠❱rs♣t②

sts s tt t ♠ r s ♦ ❱ ♥ s ♥ r♠♥t t ♦rsts ♦ t t♠♣rtr ♣♥♥ ♦ rsst♥s ♣rs♥t ♦♥ rs ♥

♥ r ♣rs♥t t t♠♣rtr♣♥♥t ♦t♦♥ ♦ ♥ t♥♥ s ♥t♦♥ ♦ t ♦t ♣♣ ♥♦r♠③ t rs♣t t♦t ♠sr t ♠❱ s ♦r tt t♠♣rtr ♦r tr♥ s ttrrss ♦ t♠♣rtr t rss t ♣♣ s s ssts tt

Page 157: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♦♦

r ❱ ♦ t ♥♥ ♦♦ ♥♦r♠③t♦ ❱0 t ❱0♠❱ ♠♣rtr ♥ ♦t s♣♥ s ♥ ♠❱rs♣t② t♥ ♥s r s t♦ t ② t ♦♥s s♣rt qr♥tssr ♥ t t①t

tr tt♦♥ ♦♠♥ts tr♠ tt♦♥ s ♥♦t sr♣rs♥ ♥ trt ♥rs ♥♦ ❯♣♦♥ ♦sr ♥s♣t♦♥ s s t♦ t ② ♠②s♣t ❱ ♣r♠tr s♣ ♥t♦ ♦r qr♥ts ♥t ② ♥ t♥ <❱< ❱ s r♥ ♥ qr♥ts ♥ ❱ s ♣♥♥ ♦ tt♠♣rtr ♦t♦♥ ♦ rt s ♥♦t ♥ qr♥ts ♥ t sss♥t② s♥♣♥♥t ❲ r st ♦r♥ ♦♥ ♥rst♥♥ ts s♦♥♦rr s♣ts t t t♠ ♦ ts rt♥

❲ ♥♦ ♦♥sr tr tt♦♥ ①♣t② ② ♣♦tt♥ s♠r r♣ ♥❱ ♣r♠tr s♣ t ts t♠ t ♥♦r♠③ t ♥ ♦♣♣ s t♦ tt ♦♥ t ♦ t♠♣rtr s r ❲ t♥ss trtrs t r② ♦ s ±♠❱ t t rs st rs t♦t ③r♦ s ♥♦♠② s r♦♠ ts tr t♥ss t♥ ≈ ±♠❱ rtr t t♠♣rtr ♣♥♥ ♣ t♦ ♦t t r t♠♣rtr ♥s t♦ r♦♣ s♥♥t② ❲ ttrt ts s♦♥ tr t♦ t ♦♥st ♦tr♠② ssst t♥♥♥ s tr tr s tt strt♥ t ♦t tr s r rt r♦♣ tt s s♣tr② ♥tr r♦♥ ±❱

❱ st② ♣rs♥t ♥ t s ♦ ♥♥ s ♦ ♥♦t ♦t♥ ♥ stst♦r② ② ♦r ♥♦♥♥♥ s t♦ s♠ r♥s t♥

Page 158: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯ ❳

r ♦ t ♥♥ ♦♦ ♥♦r♠③ t♦ t t s ♥t♦♥ ♦ t♠♣rtr ♥ t ♣♣ s ♠♣rtr ♥♦t s♣♥ s ♥ ♠❱ rs♣t②

s♠ s s r st♦rt♦♥ ♥ ❱ tsts ♦r ♥t ♦♦s ♦♦ ②♦♥ ♥ ♥stt ❱ ♣r♠tr s♣ ♦r ttr♥s♣♦rt ♥♥s ♥ ♦ t P ♥ P ♦♥rt♦♥s ♣② s st I ♠t♦♦♦② t♦ ♥♦r tr ♥ tr♠ tt♦♥s ♦ rr♥t t♥❱ s♣ ♦r P ♥ P ♥t♦♥ stts

♥♥ s②st♠

♥ ♦ t rst ♥ ♠♦st ♦♠♣t Irel rsts ♦t♥ ♦♥ ♥ ♥♥ µ♠♥ ♠tr s ♣rs♥t ♦r P ♥ P ♦♥rt♦♥s ♦♥ r ♦♥st ♠sr♠♥ts r st ♣rs ♦r rt② rs♦♥s ♦r ♦ t♠r♠♥ ♥ s s♥♥t r♥ t♥ t ♦r ♦ I rs ♦r ♦t♠♥t③t♦♥ ♦♥rt♦♥s ♥ s♣ ♦ts ♥ t♠♣rtrs ♠② s♥ rs ①t r ♣ t♥ t ♠❱ r♥ s tr s ttrt

Page 159: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♦♦

r Irel rs ♦r t ♥♥ ♥ t P t♦♣ ♥ P ♦tt♦♠rt ♠♥t③t♦♥ stt t♥ t r♥t t♠♣rtrs t♥ ♥ ♥ ♣♦tt ♥ rs♣t t♦ t t ♦t♥ r♦♠ t ♣r♥ ♠sr♠♥t t t♦r t♠♣rtr

Page 160: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯ ❳

t♦ t ③r♦ s ♥♦♠② ❩ tt s ♦♠♠♦♥② ♦sr ♥ ts ♦t r♥♥ tt rsts r♦♠ ♠♥♦♥ ①tt♦♥s st♦♥ ♦r ♦r♥ t♦r♥t ①♣r♠♥ts ❬❪ t ♠② s♦ rst r♦♠ tr♦♥tr♦♥ ♥trt♦♥s ♥ tr♥ ♦r♥t r♦♠ t ♦ tr♦♥ strtr ♠♦t♦♥ t♦ t ♠t♥st♦r tr♥st♦♥ ♦ tr♦s ♣ s ♥t② ♠♦r ♣r♦♥♦♥ ♥ t P♦♥rt♦♥ t♥ ♥ t P ♦♥ s t ❩ ♦♥trt♦♥ t♦ t ♦r ♦♥t♥t♥ t ♠♥t♦♥ ♦t r♥ rt② t♦ t st♥r t♥♥♥ s r♥ t P stt t♥ ♥ t P ♦♥ t♦ ♠ r t♦t ♦♥t♥ ♦ tttr

♥ ♥r tr♠s ♥ ①tr♠♠ ♥ ♥ I ♣rs♥t t ♥ s ❱ ♥ rtt ♦♦♥ ♣♦ss ♣♥♦♠♥ ♥ ①tr♥s ♣♥♦♠♥♦♥ t♦ s♣♥ ♣ tt♥ ♥rt ② ♠♥♦♥s t♦ t r①t♦♥ ♦ tr♦♥s t ♥r② ❱ ♦F t♦ F s ♥t ♦rs ♦r t ♥tr ♣r♠tr s♣ ♦♥sr r ts ♦♥♥ t♦ ❱±♠❱ ♥ ①tr♥s ♣♥♦♠♥♦♥ t♦ ♦♣♣♥ ♣♦♥ ts♦ tr♦♥s ♦s tt r ♦♥t♥ t t ♥r② dF❱ t tt s ♦t ss♠♥ tt tr s ♥ ss t♠♣rtr r♥ ♦r ts ♥t ♥ r♦③♥ ♦t t♥ ts ♥t ♥ ♣r♥♣ sts ♥ t t ♦♥st ♦tr♠② ssst ♦♣♣♥ s② r♦♥ > ♥ ♥tr♥s ♣♥♦♠♥♦♥ t♦ ♥s ♥ t ♥st② ♦ stts ♦ t tr♦ tt s ♦t♥ t tr♦♥ ♦r♦ t r②st strtr t r ♥st② ♥ t②♣ ♦ ts ♦ t♥t♦♥ ♣r♠ts s②♠♠tr②♦♥sr♥ tr♥s♣♦rt t♥ ♥ t s♥ ♦ tr♠②ssst ♦♣♣♥ ♦♥ ♥ ♦♥sr s②♠♠tr②♦♥sr ♥♥s ♦ ♦♥t♦♥ ♥ > ♦♥ s♦ t ♥t♦ ♦♥t t ♣♦ss ♠①♥ ♦ s②♠♠tr② ♥♥s♥ t ♥tr♣rtt♦♥ ♦ ①♣r♠♥t rsts ♥ tr s ♥ss stt t♦t ♦♠♣① ♥ strtr ♦ ♠♦st② ♦♥sr t ♥t t♥♥♥♦ ∆1 stts r♦♠ t ♠tt♥ tr♦ s ♠♣s ♦r ∆1→∆1 s②♠♠tr②♥♥ ♠♥t ♥ t s ♦ ② ♥ t♦♥ ∆1→∆5 ♥♥

♦ ①♣♦r t ❱ ♣r♠tr s♣ ♥ ② rstrt♥ ♦rss t♦ t t♠♣rtr r♥ ♦r tr♠② ssst ♦♣♣♥ tr♥s♣♦rt s s♥t ❯s♥ ts rstrt♦♥ tr♦r ♥stt t ♠♣t ♦ s♥tr tt♦♥ ♦♥ ♦♥t♥ ♥ t t♦ stts ♦ ♠♥t③t♦♥ ♥ ♦♥sq♥t② ♦♥

❲ rst ♦s ♦♥ t P s t ♦ t♠♣rtrs r♥ t r ♥ t ♥tr♥s r♠ ♦ tr♥s♣♦rt rr♥ t♦ r ♣s ♦sr t ❱ ♥ t P ♦♥rt♦♥ t ♥♦t ♥ t P ♦♥rt♦♥ ♥ r t ♦ t♠♣rtr ♠② rs♦♥② ① ①tr♥s ♣♥♦♠♥ s s t ♣♥♦♠♥♦♥ ♦ s②♠♠tr②♥♥ ♠①♥ ❲ tr♦r ttrt ts♦♥t♥ rs t♦ ♥ ♥tr♥s s②st♠ ♣r♦♣rt② ♥♠② r♥ t ♦tt♦♠ ♦ t∆1↓ ♥ trrs t t♥♥♥ ♦ s♣♥♣ tr♦♥s ♦ t ∆1 s②♠♠tr② t♦tr rs♣t s♣♥♦♥ stts ♥ t ♦♥trtr♦ ❬❪ tr C t ♦♥sst♥t② t ts ♥tr♣rtt♦♥ ♥ ♦ ♥♦t ♦sr t ♣ ♥ t Ps

Page 161: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♦♦

❲ ♥♦ tr♥ t♦ t P s t♦ t tst s♦♥ ♥ ♥s ♣ t ❱❱ ts tr s ♥tr r♣r♦ t ♣♦st ❱ ♥♦r ♥ ♦tr♥t♦♥s s♦ ♦♥t sss t rtr ❲ ♦sr ♠♥♠♠ ♦r ♣t t ❱r ♥ t♥tt② ttrt ts ♣ t♦ r♥ t ♦tt♦♠ ♦ t ∆1 ♥♥ t s♣♥♣ ♥♥ t♥s t♦ r♥ t ♦tt♦♠ ♦ t∆1↑ ♥ ♥ ♦ts ♦t t t♥♥♥ rt r♦ss t ♥t♦♥ s ①♣t t♦ rs t Atr ❲ ♥♦t tt s♠r tr ♦rs ♥ t P s t♥ ❱ ♦ tt♥ t P s tr ♥ t P s ♥♥♦t ①♣♥ s♥ ♥ ♥tr♥s♣♥♦♠♥♦♥ t ♦ rt t t tt ts ♦ P I ♠♥♠♠ s tr②t rst ♦ ♥ s♣tr② ♦t t♥ t♦ ♠①♠ ♥♥ ♦♥ ②♦♥±❱

♦ ♦♥ ts ♣rt ♦♥ ♥tr♥s ♣♥♦♠♥ tt r rt♥ t♦ ♦r t♥t ♦ t♠♣rtr r♥ ♦♥sr t♥ss trs ♥ t P s tt ♠② ♦♥♥t② sr t♦ ♥ strtr ts t♦s ♥ t P s r ♠♦rt t♦ ♥♠♦s② ttrt

❲ ♥♦ ♦♥sr t t♠♣rtr r♥ ♦r ①tr♥s ♣♥♦♠♥ ♠② t ♣ ♥♦t② ♥♦♥ ts ♦ ttr ♦♦ t ♥②ss r♣r♦ ♦♥ ♥ ♥ ♥s ♥s♣ ♦ ♥rt ♣♦st♦♥ ♦ s♣ ts♥ t rrr s s ♦♥ ♥♦r♠t♦♥ ♣r♦ ♥ st♦♥ ♦♦♥ ♥②ss ♦ rsts ♣r♦s ♦♥ t ♠♣♦rt♥t ②♣♦tss tt s s♦♥♥ t r♠ s t t ♥tr ♦ t ♦♣t ♥ ♣ t♦r ♥trt② ♦♥srt♦♥s ♦r t ♣♥♥♥ str♥t ♦ t r ♥trt② ♣♥s ♦♥ t t t②♣ ♥st② ♦ ts t♥ t rrr s s tr s♣t ♦t♦♥ ♦s t♦ ♦♥ ♥tr ♦r t ♦tr ♦r ♥ t ♠ st t ♣♦st♦♥ ♦ F ♠② r♥t ♥ t♥ ♥♦♥♥♥ ♥ ♥♥♥t♦♥s t ♦♥ ♥ ♦♠♣r t sts ♣r♦r♠ ② ♦tr r♦♣s tr♥♠♥t ①r② ♣♦t♦tr♦♥ s♣tr♦s♦♣② ♦r s ♥ t ♦♦s ♣r♦ ts ♥tr♣rtt♦♥ ♦ ♦r rsts tt s ♦♥sst♥t tts rs♦♥ ♥rt ♣♦st♦♥♥ ♦ t r♠ ♥ ♦r s

❲rs t rt I P t t r r r♠♥s s♠r t♦t ♦♥ t ♦r t♠♣rtr t ♦♥t♥ ♥ t P ♥♥ ♦♠s♦♠♥t ② ❱ tr tt t ♥rs♥ t♠♣rtr ♦♠♥t t♦♥t♥ rs t t♠♣rtr ♥trs s tr s♦ ♣♣rs strt♥r♦♠ ♥ t P ♦♥rt♦♥ t r♥ r ♥ t ♣♣r♥ ♦ tstrs s ♦♥② tr♠② rt ss♦t t ♣ t t ♦ t♥♥♥ F ♥ F+ ♥trs tt ❱ ♦ t ♦tt♦♠ ♦ t ♦♥t♦♥ ♥ ♠♥♥

♥ ♣r♥♣ t t s♦ ♦♥r♥s s♣♥♦♥ tr♦♥s ♦ t ∆2′,5 s②♠♠tr② s t ♦tt♦♠t♦♣ ♦ ts ♥ s r ♥ t P ♦♥rt♦♥ t ❱ ❱ s ♦rrs♣♦♥s t♦ t B

E tr t ♦r ♦ ♥♦t ♦sr ts trs t♥ t t♠♣rtr r♥♦rrs♣♦♥♥ t♦ ♥tr♥s tr♥s♣♦rt ❲ s♣♣♦s tt t♦ ② rt ♦ tr♦♥s ♦ tss②♠♠trs tr ♦rrs♣♦♥♥ ♣s r ♥♦t s ♥ t t

tr r♦♥ ♦ ♥t♦♥s t r ♦ts ♣r♥t rt♦♥ ♦ ts ♣♦♥t

Page 162: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯ ❳

r ♦s ♥r② ♥s♣ ♦ ts ♥ t rrr s♠r t♦tt ♣rs♥t ♦♥ rs ♥ trs ♥♦t ♦sr ♥ t ①♣r♠♥t rr② ♦t ♦r rt② rs♦♥s ♥ ♣ ♦ t ♦ rrr s ss♠ t♦ ❱ ♥ t r♠ t♦ ♥ ts ♠

❱ ♦ t r♠ s s♥ ♥ ❲ t♥ tt t rs♦♥ ♦r t ❱ tr s ♥♦t s t ♥

t P ♥♥ s ttrt t♦ ts ♦rs♦♥ ② t ♦r♠♥t♦♥ ♥tr♥str tt s s♣tr② ♦s t t♠♣rtrs ♥ r t s t ♥tr♥st tt ♦♠s ♦rs♦ ② t t♠t t♥♥♥ s s rtrsst ② t ①♣t♦♥ t ♦ ❱ ♣s ♥ t t♠♣rtr r♥♦♠♣r t♦ ts t ♦tr t♠♣rtrs s s♥♥t ♥♥ ♦ F ♥ F+

t sts ♦♥ ♦♥t♥ r♦ss r②st♥ rrrs s ♥ r♠♥t t ♦rsts ♣r♦r♠ ♦♥ r②sts ♣rs♥t ♥ st♦♥

Irel st② ♦ ♥♥ ♥t♦♥s t t♠♣rtrs r t♥ s♦s

♦♠♥② t♦ t t♥ss ♦ t ♦♠♣① ♥ strtr ♦ r♦♥ ♠♣ t ♦♥ tr♦♥ t♥♥♥ s♦ ♥st♥s s ♦♥ s t t ♦s ♥♦t r② ♦s t♦t t♦♣ ♦ t ♥ ♥ r t ♦ r ♣r♦t② ♦ ♥ ♦ t ∆5 s②♠♠tr②s

Page 163: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♦♦

r Irel rs ♦r ♥ ♥♥ ♥ t P t♦♣ ♥ P ♦tt♦♠rt ♠♥t③t♦♥ stt t♥ t r♥t t♠♣rtrs t♥ ♥ ♥ ♣♦tt ♥ rs♣t t♦ t t ♦t♥ r♦♠ t ♣r♥ ♠sr♠♥t t t♦r t♠♣rtr rs r ♣♦tt ♥ t ♦rt♠ s ♦r rt② rs♦♥s

tt t ♠①♠♠ ♦sr t ♦r P ♥ P ♦♥rt♦♥ t ❱ ♠♦st♦rs ♦r ♦ts ♦♥ t t t♠♣rtr rs ❲t♥ t r♥ t rs ❱ ♥ t P ♦♥rt♦♥ ♥ ❱ ♥ t P ♦♥rt♦♥ s st ♠② ①♣♥ s t rst ♦ t r♦♥ ♦♠♥♥ t♥rs♥ t♠♣rtr t♥ t r♥ ♥ s♣② t♥ ♦ tr♥s♣♦rt tt s ssst ② t ①t stt F+∗ t ❱ ♦ F s t♦ t tr♠♥t ♦ ts r♦♥ stt ♦♥tr♣rt F+ ♥ tr♥ ts ♦①♣♥ t ♥ ♥ t tr tt♦♥ tr♥ ♦sr t ♥ t

Page 164: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯ ❳

t s♠ s ♦r ♥r② ts t♠♣rtr♥ ♥ ♥ t t②♣♦ t tt ♠ts ♦♣♣♥ tr♥s♣♦rt ♠② ①♣♥ t t♦♥ rs ♥P ♥t♦♥ rsst♥ ♥ ss♦t t ♦ s ♣st t tt♠ ♦ ts rt♥ r ♥tr♣rt♥ ts rsts ♣♦t♥t② ♦♥sttt♦♥s t tr ♥tt♦♥ ♦ t stts sr ♦ ♦rr♦♦rt♥ tr♠ ♥tt♦♥ t♥ t ♦♥t①t ♦ t♠♣rtr ♣♥♥t ttt♦♥ ♣r♦sss s sss ♥ r ❬❪ ❲ ♥♦t ♦r tt t ♣♥ t P ♥♥ t ♦rs t ❱ t s r♥t r♦♠ tt ♥ t Ps ♦♥sst♥t t ♦r ♥tr♣rtt♦♥ ts ♦ ♠♣② tt t rt ts♦ t FF+ ♥ F+∗ tt♦♥s t♥ ❱ s♣ r ♥♦t t s♠ ♦r P ♥P t ♣rs♥t r ♥stt♥ ts r♥ ♥ tr♠s ♦ s②♠♠tr②♣♦r③tr♥s♣♦rt ♥♥s ♥ ♦♥rt♦♥

♥♦♥♥♥ s②st♠

❲ ♥♦ ♦♥sr r♣rs♥tt tst ♦r r♦♠ t ♥♦♥♥♥ s♠♣ Irel rs ♦t♥ ♦♥ ♥♦♥♥♥ ♦ µ♠ ♠tr r s♦♥ ♦♥ P ♥ P ♠sr♠♥ts s♦ r② s♠r rtrsts t ♦♥② s♥♥t r♥ ♥ t t ♦ t ③r♦ s ♥♦♠② ♣ s ♦♦s②♠♦r ♣r♦♥♦♥ ♥ t P ♦♥rt♦♥ s s♠r ♦r ♦r P ♥ P Itst ♦sr ♦r ♥♦♥♥♥ ♥t♦♥s s ♥ ♦♥trst t♦ tt ♦r tr ♥♥♦♥tr♣rts rtr♠♦r ♥♥ s ♦ ♥♦t ①t st♥t ♥tr♥s ♥①tr♥s tr♥s♣♦rt r♠s t♥ t ♣r♠tr s♣ ♦ t♠♣rtr ❲ tr♦r s♣♣♦s tt t♥ t rrr ♦ ♥♦♥♥♥ ♥t♦♥s tr♥s♣♦rt st♦♠♥t t t♠♣rtrs s s ♦♥sst♥t t t ♠♦♥♦t♦♥ rs t ♥rs♥ t♠♣rtr ♦sr t ♦ s s

t♦ t s♠ ♦♥② r♥ ♦ t rst ♠sr♠♥t t r ts rs♦t♦♥ s rt② ♣♦♦r t r♦ ♣ s ♦sr ss♠ t♦ rst r♦♠ ♦♥♦t♦♥ ♦ t♦ ♣s ♦♥ t ❱ ♥ ♦♥ t ❱s ♥tr♣rtt♦♥ s s♣♣♦rt ② t t♠♣rtr ♦t♦♥ ♦ t rt I t ♥t t ♣rs♥ ♦ ts t♦ trs ♠♦r r② rst ♣ t❱ ♠② ♦rrs♣♦♥ t♦ t tr♠② tt t♥♥♥ r♦ss FF+ tsts r② ♣rs♥t ♥ t s ♦ t ♥♥ s♠♣ ts ♥♥ ♦♥ t♦♥t♥ s♠s t♦ ♣rsst ♣ t♦ t r♥ r tr t ♦♠s② ♦rs♦ ② t tr t ❱ ♦♠s ♣r♦♥♦♥ ♠♦r t tt♠♣rtr ♥rs ❲ ttrt ts ♣ t♦ t ①t ♦♥③ ♦①②♥ ♥② t F+∗ ♥tr s

r s♦s t t♠♣rtrs Irel tst ♦t♥ r♦♠ ♥♦♥♥♥ ♥t♦♥s t t s♠ ♣r♦♣rts s t ♦♥ ♦r t ♦ t♠♣rtrst② s ♣rs♥t ♠sr♠♥t s s♦ ♣r♦r♠ s♥ t ♣♦♥t ♦♥tt♠♦ t s ♥t tt ♦ t ♦♥t♦♥ rs t F+∗ ♥tr ♦♠s♦♠♥♥t ♣ t♦ ♦r ♦t ♠♥t ♦♥rt♦♥s trrs t ♠①♠♠

Page 165: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♦♦

r Irel rs ♦r ♥♦♥♥♥ ♥ t P t♦♣ ♥ P ♦tt♦♠rt ♠♥t③t♦♥ stt t♥ t r♥t t♠♣rtrs t♥ ♥ ♥ ♣♦tt ♥ rs♣t t♦ t t ♦t♥ r♦♠ t ♣r♥ ♠sr♠♥t t t♦r t♠♣rtr sr♠♥ts r ♣r♦r♠ s♥ t ♣♦♥t ♦♥tt ♠♦

Page 166: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯ ❳

r Irel rs ♦t♥ ♦♥ t s♠ ♥♦♥♥♥ s ♦♥ ♥ t P t♦♣ ♥ P ♦tt♦♠ rt ♠♥t③t♦♥ stt t♥ t r♥t t♠♣rtrs ♣ t♦ ♥ ♣♦tt ♥ rs♣t t♦ t t ♦t♥ r♦♠ t ♣r♥♠sr♠♥t t t ♦r t♠♣rtr sr♠♥ts r ♣r♦r♠ s♥ t♣♦♥t ♦♥tt ♠♦

strts t♦ st t♦rs ♦r ♦ts r♥ ❱ t s s ♥♦t② ♦rt♥ t s ♦sr rr♥ ♥♥ s ♥ ♣r♥♣ F2 stt ♠②♣r♦ s♣tr t t♦ t I t ❱ s tr② ①♣♥♥ t st

Page 167: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♦♦

t ♥♦t ♥♦r r♠ sttst② r♥t ♥ ♦ ts t stt♥ ♦r ♠♥t♦tr♥s♣♦rt ①♣r♠♥ts

♦r ♥r② ♦r ♠♥t♦tr♥s♣♦rt ①♣r♠♥ts s♦ ♦ ♥♥ s♠♣s♥ ①t t ♦ t♠♣rtr ♠♥t♦tr♥s♣♦rt r♠ tt s ♥tr♥s ♥ t♠t tr♥s♣♦rt s ss♥t② r♦③♥ ♦t ♥ ♦♥trst t♦ ♥♦♥♥♥s♠♣s ❯♣♦♠♥ P ①♣r♠♥ts t ♥t ♣ ♦ ♣r♦♥ ♥♦t s♠♣②F2 t F F+ F ∗ ♥ F+∗ ♥trs ♠② s♥ ♥ t♦♥ t ♣♦♥ t ♣②ss♥r♥t

♦ ♦♥ ts st♦♥ ♦r ♠♥t♦tr♥s♣♦rt rsts ♦♥ ♦ ss ♥ tr ♦♠♣♥②♥ s♦♥sst♥t ♥②ss s♦ tt tr♦ sttr ♥♦r tr♠ tt♦♥ s♣ rs♦♥② ♥t t stts♣rs♥t t♥ t t♥♥ rrr ♠② ♣rt♣t ♥ s♣♥♣♦r③ tr♥s♣♦rts t stts ♣♣r t♦ rs♣♦♥s t ♦ s ♦r t rs t♥rs♥ t♠♣rtr tr♦ t♦ s♣rt t♠♣rtr r♠s ❲ r ♣rs♥t②♦r♥ t♦ sr ♥ t♦♥ tr♠ s♥tr t♦ t tr s♥tr ♦ tst stts

Page 168: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯ ❳

Page 169: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

Prt ❱

♦♥s♦♥s ♥ ♣rs♣ts

Page 170: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue
Page 171: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♣tr

♠♠r②

s ♣tr s♠♠r③s t ♦r ♣r♦r♠ t♥ t t♠r♠ ♦ ts tss♦♥ ♠♥t t♥♥ ♥t♦♥s ♦♥sst♥ ♦ tr♥st♦♥ ♠t ♦① ♥ ♦♥ ♠♥s♠ ♦① trs s tss r♣rs♥ts ♦♠♣♥♠ ♦ ♦r ♦♠♣s♦♥ t rsr ♥ ♦♥sst♥ ♦ s♠♣ r♦t ♥ rtr③t♦♥ t♥♦♦ ♣r♦ss♥ ♥t♦ s ♥ ♠sr♠♥t ♦ ts s

t t ♦♥st ♦ ts ss s♦♠ ♣r♠♥r② ♦r t♥ ♣ t♦rs②♥ts③♥ s s ♦♥ sts ♣♦st ② P t t P ②r♠t♠r s②st♠ ♥ ♦♥② r♥t② ss♠ ♥ ♥ ♣rtr ♦♥②r♥t② t s♣ttr ♠r ♥ t♦ ♦♣rt ② s ss ♥♦①♣♦r♥ t r♦t ♣ts ♦ ♦t ts ♣♦st♦♥ s②st♠s ♥ ♣rtr t②r s♣ttr♥ s②st♠ t♦r ♠♥ ♥♦r♥ s♣♥tr♦♥ sts

t t ♦♥st ♦ ts ss t rt ♦ ♣r♦ss♥ s♠♣ sts ♥t♦ t♥♥♥t♦♥s st ♣♣r t t P ②t ♦♥sst♥t ♣r♦t♦♦ ♥t ②t ♥ ♥♦t② t♦r ♣r♦ss♥ s♠ s♠♣s s s t♦s r♦♠ t P srs ♦ trt♦♥s t♦ ♦t t ❯❱ ♥ s♦ ♠ss t♦ ♠♣r♦ strtrs

♥t♦tr♥s♣♦rt ♠sr♠♥ts ♠ r♦t♥ ♣rt ♦ t rsr ♦r♦ ♦♥str♠ ♥ ts rsr ♥ ♠② tr♦ ts ss t♥s t♦ tss♠② ♦ t ♦♣♥ss rt ♥

s s t s♠♠r② ♦ s♥t rsts ♦r ts tss tt r ♣rs♥t rtr ♥♦♠♣sss ♦t ♠trt♦♥ ♦ ♥rstrtr rsr ♣ts ♦♥s s♥t ♣r♦r♠ t♦ ♦♠♣s ♦♥ ts rsr ♥ ♦rr♥ ♦ s t♦ ♥rst♥ t ♠♣t ♦ ts ♦♥ ♠♥t♦tr♥s♣♦rt r♦ss♥♦r♥ t♥♥ rrrs

r♥st♦♥ ♠t ♦①s

s tss ♥stt ♠♥t t♥♥ ♥t♦♥s s ♦♥ tr♥st♦♥ ♠t ♦①rrrs t ♥ ♠♣ss ♦♥ ♣r♥ ts rrrs t tr♥st♦♥ ♠t tr♦s

Page 172: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯❨

s s ♦♥ r3 ♥ 2 rrrs r st ♦2r3♦2strtrs rt t t P s②st♠ s♦ ♦ s♣♥tr♦♥ ♦r♥ rs♦♥s ♦r tr ♠♦rt ♣r♦r♠♥ r ♥t ♥ tr♠s ♦ ♥tr♥ s②♠♠tr② tr♥ sss ♦r♦r t t♠♣rtr ♣♦st♦♥rst ♥ t ② ♦①t♦♥ ♦ ♥trs s♦ s t♦ ①♣♥ ♥ ♣♣r♥t t♥♥♥♦r ♣r t t s♥ ♦ ♥ ♥ tt♠♣t t♦ s♦ ts sss tr3 rrr s r♣ t 2 t♦ ♥sr ♦♠♦♥♦s rrr ♣r♦sttr♠♥t♦♥ ♥ t♦♥ ♦t ②rs r ♥srt t ♥trs s ♦♥ t sts r ♣r♦r♠ ♦♥sst ♦ ♦22♦2 ♥ ♦2♦sts rs♣t② ❯♥♦rt♥t② ts s②st♠s ② s③ s♥ ♦♥②t ♦ t♠♣rtr ♥ tr srt♥ ♥♥♥ ♦ t s ♥rs trrsst♥s ② ♣ t♦ ♦♥ ♦rr ♦ ♠♥t t s t ♠♥t♦rsst♥ t♦♥s ♥tr② I ♠sr♠♥ts ♣r♦r♠ ♦♥ ♦t t②♣s ♦ s s♦ r②♥♦♥♥♦r♠ ♥ ♦ ♦♥ t♦ ❱ rrr ts r t st② ② ♥rt♥ ss s♠♣s t r♣r♦ ♣ t♦ t r♦♦♠ t♠♣rtr ♥♥ ♥st♥s s tt r ≈ ± t ♦ t♠♣rtr t♥s t♦srt♥ ♦ t st ♦ ♦r ♥♦ ts rsts ♦♥sttt t stt♦trt rr♥ tr♥st♦♥ ♠t ♦① rrrs ♣r t tr♥st♦♥ ♠t tr♦s

①ss 2·10−7♠r ♣rssr r♥ ♦r tr♦ ♣♦st♦♥ s ♥ts t ♠♥ rs♦♥ ♦r t ♣♦♦r ♣r♦r♠♥ ♦ ♦2 ♥ ♦s s sss ♦ ♥♦t ♣rs♥t 0.7r0.3♥3 s s s t ♦r tr♦ t♦ t st② ♦ s s ♠s t♥ ts st② ①t rt♠♣rtr ♦ tt s rs♦♥ ♦r ts s②st♠ ♦r ♦r st② s♦♥ tt ♥♦rt♥t② t ♣rs♥t P tr s♥ ♥ ♣♠♣♥ sts ♥♦t ♦♠♣t t t ♦①②♥ ♣rt ♣rssrs rqr t♦ ♦t♥ ♠s t ♦①②♥ ♦♥t♥t tt r♠♥s st ♣♦♥ t♦r♣ ♣r♦ss♥♥ ts s♣t sr tt♠♣t ♥s ♥ t r♦t ♦♥t♦♥s

♥s♠ ♦①

❯s♥ t s♣ttr ♠r ♦ t P ②r s②st♠ ♠s r r♦♥ r②♥ t ♦①②♥ ♦♥t♥t t♥ t r♦♥ ♣s♠ ♣t sts r tt♣♦♥ ♥rs♥ t ♦①②♥t♦r♦♥ rt♦ ♦♣t s♦r♣t♦♥ t♦ s♣ tt②♣s ♠♥ss s♥♥t② ♥rs♣♣r♥ ♦ ♦♥t F ♥ F+

♥trs s ♦♥r♠ ② ♦ ♠sr♠♥ts ♥ ♥tr♦♥ ♦①②♥ t♦ r♠t ♠♣r♦♠♥t ♥ t t♥♥♥ qt② t♦t tr♥ tst♦♣♦r♣② ♥ s ttrt t♦ rt♦♥ ♦ t t sts ♦♥♥trt♦♥♥ rtr ♦♥r♠ tr♦ rr♥t♦t rtrsts s♣tr♦s♦♣s♥trs ♣rs♥t ♥ ♦t t ♦♣t ♥ ♦ t♥♥♥ sts ♥♠♦s②sr t ♠♣t ♦ ♥tr♦♥ ♦①②♥ r♥ r♦t t♦ t ♣♦♣t♦♥rt♦♥ ♦ s♣ ♥t ts s s ts s♦ ♦ ts

Page 173: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

❯ ❳

t♥ t rrr ♥ ♦♥tr♦rt♦♥ ♦ s s ♣ttr♥ ♥ st r♥ t r♦t t♦t

t ♥ ♦r rtr ♣r♦ss♥ ② ♦♣t t♦r♣② s tt♠♣t ♥t♦ ♥t ts rst ♠♦st② ♥ s♦rt s sr t♥ ♠♣r♦♠♥ts r t♦ t r♦t ♣r♦r ♥ s t t t♥♥♥ r♠♥ stst♦r② rrr ts r ♥② ♦t♥ t♦ t ♥t♦♥s ♥♦t② ♥② s♥ ♠♥ rs♦♥ ♦r ts str s♣♥tr♦♥ ♣r♦r♠♥s ttrt t♦ ①ss ♦①t♦♥ ♦ t ♦r tr♦ t♦ 10−7 ♠rr♥ ♣rssr r♥ t ♥♥♥

♦s s♠♣s r r♦♥ ② ♥ t t ♥sttt ♥ ♠♦r ♥ ♥② r ♦ t♠ r ♥♥ ♥ ♦rr t♦ ♦♠♣r t ♠♣t ♦ts ♦♥ tr♠♥t♦rsst ♣r♦♣rts ♥♥ s s♦ s♥♥t② r rt♦ ♦♥ t♦ t t①tr③t♦♥ ♦ ♦t t rrr ♥♥tr ♦ ②rs s rs t♦ ♠♣r♦ s②♠♠tr② tr♥ ♥ ♦r♥t tr♥s♣♦rt r♦ss t r②st♥ strtr ② ①♣♦r♥ ♦ tr ♥tr♠ tt♦♥ ts r ♥ s♣♥♣♦r③ tr♥s♣♦rt s♦ ♦ t s♣♦ss t♦ tr② rss t stts r rsts t♥tt② s♦ tt tst stts ♣② ♥ ♠♣♦rt♥t r♦ ♥ ♠t♥ ♥ t ♣r♦ss s ♠♥ t t♦r r♦♥♥ t s♣rt ♠sr♠♥ts ♦ rrr ts r♣♦rt ♥ t s ♦trs ♦♥sr t ♠♦st ♠str t♥♥♥ s♣♥tr♦♥s②st♠

Page 174: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P ❯❨

Page 175: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♣tr

♦♠♣

❲t♥ ts ♣tr ♣rs♣ts ♦ rtr ♦♣♠♥t ♦ sts ♣r♦r♠ r♥ts tss r ♣r♦♣♦s ② ♥♦♠♣ss ♦t ♣r♦♣♦s ①t♥s♦♥s ♥ ♠♦t♦♥s t♦ r♦t st♣s s s ♣r♦♣♦s rt♦♥s ♥ t rt rsr♠② ♣r♦

r♥st♦♥ ♠t ♦①s

Prs♣ts ♦ sts ♦♥ tr♥st♦♥ ♠t ♦①s t♥ P r♠♥ ♠♦st② ♥ss ♦ t ♠tr s♥ ①♣r♠♥ts ♣r♦r♠ t♥ t t♠r♠ ♦ tstss s♦ tt trt♦♥ ♦ rt♥ s♣ts ♦ t P r♦t r ss♥t ♥♦rr t♦ ♦t♥ s t ♣r♦♣rts sr r♦♠ t s♣♥tr♦♥ st♥♣♦♥t

2 ·10−7 ♠r ♣rssr r♥ t ♣♦st♦♥ ♦ ♦r tr♦ ♠trs ♥s t♦ r ♥ ♦rr t♦ r♦ qt② ♦2 tr♦s t♦t ♥tr ♦①t♦♥ ts ♥♥♦t ♦♥ t tr♥t ♥ ♦r♠ ♦ 0.7r0.3♥3 s ss ♥t♣t ♦r sss ♦ ♦①②♥ st♦♦♠tr② ♥ ♦①②♥ rt♥t♦♥ t♥t ♠ r♥ t♦r♣② ♥ t♦ rss ❲ ♣r♦♣♦s st ♦♦♣t♦♥s t♦ ♥stt ♦r ♥r② t♦ t ♦r ♥ ♣ ♦ tr♥st♦♥ ♠t♦①s ♥ ② rt ♦ tr ♠♦r ①♦t ♦♠♣① ♥ strtr tr♥st♦♥ ♠t♦①s ♠♥t t♥♥ ♥t♦♥s ♦♥sttt ♣r♦♠s♥ tst s②st♠ ♦r ♠t♥t♦♥ s♣♥tr♦♥s tt ♦♠♥ ♠♥t tr ♥ ♦♣t ♥t♦♥tss rtr

♥s♠ ♦①

♥ tr♠s ♦ ts st② t♥ tr r②sts sr rtr st♣s r ♣r♦♣♦sr♥ t ♠♣t ♦ s♠♣ ①♣♦sr t♥ t r♦t ♥ rtr③t♦♥tr♠♥♥ t ♦t♦♥ ♦ t ♥ ♣ r♦ss t♦♠ ♣♥s ♥ t♦♥ st②♦ t sr♥tr ♥tr ♦ ts ♥ t♥ ♠s ♦s tr♥st♦♥ ♥rs ♥

Page 176: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P

♣♦st♦♥s t♥ t ♥ ♣ r r♥t r♦♠ t♦s ♦ t ♥ r♠♥ r②♥st s sts r st ♦r t r t♠♣rtr tt ♦♥♥t t♦ t ②r s②st♠ ♥ t ♥r tr

♠r② t♦ t P r♦t t♥q t rtr ♣♦♦r s♣♥tr♦♥ ♣r♦r♠♥♦ t s♦♠ss s s t♦ ♠♣r♦ ② rs♥♣rssr ♥ t ②r ②st♠s ♠r r♥ t ♥♥♥ ♦ t ♦r tr♦♥ ♠② ♠♣r♦ t ♠ ♣♦t♥t② ② ♦ttt♥ t s♣ttr ♠rs ♠♥st t r♥t ♣♠♣♥ ♥ ♠② s♦ ♣♦t♥t② ♦♥sr r♣♥ ♥ ♦ tr♦s t ♦ ♦♠♣♦♥s s♦ s t♦ r♠♥t ♦①t♦♥ sss tt ♥t♦♥ ♥tr

①♣r♠♥ts ♣r♦r♠ ♦♥ ♦s s ♣♣r t♦ r② ♣r♦♠s♥sss rt t♦ t t ♥②ss r♠♥ s♠r t♦ ts rt t♦ ♦ r②sts t ♣tt♦♥ ♦ ♦r ♠♦ ♦ t t ♥s♣ ♥ r②st ♦r tt♥ ♠s ♥ t♥ ♥tr ♥tr ♦ ts ♥t♦ t ♦♥t ♦rrt♦♥t♥ s♣rt② ♦♥t ♦♣t ①♣r♠♥ts ♥ ♠♥t♦tr♥s♣♦rt ①♣r♠♥ts s t♦ t♥tt② ♣♦st♦♥ t r♠ ♦ t tr♦s rt t♦ t♥ ♥ ♦♥t♦♥ ♥ s ♦ Pr♦r♠♥ ts ①♣r♠♥ts ♦♥t②♦ rt② ♣ s♦ ts ♠♣♦rt♥t ♣♦♥t s rtr ♥ tr♠s ♦ t tr st② sr t♦♥ s②st♠s r ♣♥♥ t♦ tst ♥ ♦♦♣rt♦♥t ♥sttt ♥ ♠♦r ♥ ♥② s ♥ ♥t♦♥s t sr ①ss t♥sss t strt② ♥t② ♦♣ ② ♦♥ r♥ s ssrr♥ s ♥ r♥t② r♣♣ t♥ t ❯P② r♦♣ ♥ t s♦ s ♥ ♦rr t♦ st② s②st♠s ♥ t ♦♥t♥ s r③ t sts ♦♥② ♦r ♥r② ts rsts ♥ t s♥t ♠t♦♦♦② tt♥rs♦rs t♠ ♠② r♣♣ t♦ ♦tr ♦①s ♥♦t② t♦s t ♥♦♠♥②①♣t rr♦trt② ♦r ♠trr♦t② s♦ s t♦ ♥rst♥ t♦ t ①t♥t ts♥tr♥s ♠trs ♣r♦♣rts r ♦r♥ ♥ s ② ts

♣t ss

r♥ t t♠ ♦ t rt♥ ♦ ts ♠♥sr♣t r♥ ♥ st♦♠♠ st♣ t♥t♦♥ ♥ ♥ t♦♥t♦♥♥ ♥ r♥ ♦r s ss♠ ♥ s t t t♠ ♦ ts rt♥ ♦♣rt♦♥ t ♥♦♠♥ ♠♥t♦tr♥s♣♦rt♥ r♠♥tr② ♦♣t ♣ts t s s♥ t♦ ♥ ♦♠♥ ♦♣t ♥tr ♠t♣①♥ sts ♦♥ s s s ♠♥t t♥♥ ♥t♦♥s st♣ ♥ts r♦♠ rt② ♠♦r♥③ s♥ ♦♠♣r t♦ t rt st♣s♦ t t③s t s♠ ♣ s♥ ♦r t ♦s t♦ ♣s t♦ ♠♦♥t ♥♠sr s♠t♥♦s② r♦♦t ts ss t ♦s s ♥ t♦ t③ ts♥ ♦♥ ♦♣rt♦♥ t♦ ①♣♦r t ♥tr♣② ♦r ② t stts t♥t t♥♥ rrr t♥ t ♠♥t tr ♥ ♦♣t ♥t♦♥ts ♥ ♠♥t t♥♥ ♥t♦♥ ♦r ts ♥ ❯❱ t♦r♣② ♠ss r s♥

Page 177: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P

strt♥ ♥ r② s♦ s t♦ ♥ ♦♣t ss ♥ r ♠♣r♦ s ①♣rtss tt♥ ♦♥ ♦ t♦ st ts ♦♣t ss s ②♦ r ts ♥s s♦ ♣r♦r♠♥ t rst ♦♠♥ ♦♣t♦♠♥t♦rsst ♠sr♠♥ts ♦♥t ♠♦ ♥♦r♥ ♠♥t t♥♥ ♥t♦♥ s②st♠ ♦♦ t②t♥

Page 178: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P P

Page 179: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

♦r♣②

❬❪ ♦♦r r♠♠♥ ♠♦r ♦♠♣♦♥♥ts ♦♥t♦ ♥trt rts r♣r♥tr♦♠ tr♦♥s ♦♠ ♥♠r ♣r ♣♣ ♦ttrts sttr ♦ ♣♣ s♣t

❬❪ r♦t♦ rt ❱♥ Ptr♦ P t♥♥ r③t rr ♥ ③s ♥t ♠♥t♦rsst♥ ♦r ♠♥t s♣rtts P②s tt ♦ ♣♣ ♦

❬❪ ♥s P rü♥r r♥ ♥ ❲ ❩♥♥ ♥♥ ♠♥t♦rsst♥ ♥ ②r ♠♥t strtrs t ♥trr♦♠♥t ♥tr②r①♥ P②s ♦ ♣♣ r

❬❪ Pr♥ ❳ ♥ sr P♥ ♦ ♥ ♠♥t ♥t② ♥♥r s♣♥tr♦♥ s♥s♦rs ♥ ♠♠♦r② Pr♦♥s ♦ t ♦ ♣♣ ♠②

❬❪ P r♦ ♥ sr② ♣♥ ♣♦r③t♦♥ ♦ tr♦♥s t♥♥♥ r♦♠♠s ♦ ♦ ♥ ♥ P②s ♦ ♣♣ ♥

❬❪ P s♣r♦♥tt② ♥ t♥ ♠s ♥s ♥ P②ss♦ ♥♦ ♣♣

❬❪ ♦♦r ♥r ❲♦♥ ♥ sr② r ♠♥t♦rsst♥ t r♦♦♠ t♠♣rtr ♥ rr♦♠♥t t♥ ♠ t♥♥ ♥t♦♥sP②s tt ♦ ♣♣ ♣r

❬❪ ❲♥ ♦r♠♥ t♦♥ ❩ ♥ ♥ ♥ t♠♣rtr♦r st s♥ ♥t♦♥s t ♦ s r ♥ rr♥ ②rs ♥ts r♥st♦♥s ♦♥ ♦ ♣♣ ②

❬❪ r♥ ❲ tr ♥ ❳ ❩♥ ♣♥♣♥♥t t♥♥♥♥ ♣t① s②st♠s ♥ ♣♥♥ ♦ ♦♥t♥ ♦r♥ ♦ ♣♣P②ss ♦ ♥♦ ♣♣

Page 180: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P❨

❬❪ t♦♥ ♥ ❯♠rs ♦r② ♦ t♥♥♥ ♠♥t♦rsst♥ ♦ ♥♣t① ♠♦ ♥t♦♥ P②s ♦ ♣ ②

❬❪ ♦♥ ❱ r♦s Ptr♦ rt ♦t ♦str♠r ❱ ♥t ♦ r♦♥s rs ♦r♦♥ rr Pr♦ ♥ ♦r♥t r ♠♥t♦rsst♥♥ ♠♦♦ ♣t① t♥♥ ♥t♦♥s ♦♥ s ♣♣ P②ssttrs ♦ ♥♦ ♣♣

❬❪ P♦♣♦ r❱♥♥t s♥ ♦r sr ♥ ♦♥t♥ ♥♦t ♥r ♥♦ ♥ ❱ ♦st♣t① ♠♦ ②r ♦r ♦rsst♥ ♥ ♦♣♥r ♠♥t t♥♥ ♥t♦♥s ♣♣ P②ss ttrs ♦ ♥♦ ♣♣

❬❪ ❨s s♠ ♠ ♥♦ ♥ ❨ ③ t♥♥ ♠♥t♦rsst♥ t r♦♦♠ t♠♣rtr ♥ ② ♣t① ♠♦ t♥♥♥t♦♥s t♦ ♦r♥t s♣♥♣♦r③ t♥♥♥ ♣♥s ♦r♥ ♦ ♣♣ P②ss ♦ ♥♦ ♣♣

❬❪ ❨s ♥ ②♣rr ♥t t♥♥ ♠♥t♦rsst♥ ♥ ♠♥t t♥♥ ♥t♦♥s t r②st♥ ♠♦ rrr ♦r♥ ♦ P②ss ♣♣ P②ss ♦ ♥♦ ♣

❬❪ ② ❨ s③ ❨ r s s♥♦ tsr ♥ ♥♦ ♥♥ ♠♥t♦rsst♥ ♦ ② s♣♣rss♦♥ ♦ t s♦♥ ♥ ♦♠♦♦ ♣s♦s♣♥s ♥♥ t t♠♣rtr ♣♣ P②ss ttrs ♦ ♥♦ ♣

❬❪ Pr ❱s♦♦ ♠ ♦♥ ♠s ♥ ❱♥ts♥rt ♥ ♦r ♠t rr♦♠♥t tr ♦♥♦♥ ♦ ♣

❬❪ ♦♥ s rt♠② P ♦♥t♦r ♥♥ ❨ ♠tr♥ rt r② t♦t s♣♥ ♣♦r③t♦♥ ♥ ❬s ❪sr❬s ❪♠♥♦❬s ❪r♦♠ t♥♥♥ ①♣r♠♥ts ♣♣ P②ss ttrs ♦ ♥♦ ♣♣

❬❪ t♦ s ♥ ♥♦ ♥t♦rsst♥ ♦ rr♦♠♥t t♥♥♥t♦♥s ♥ t ♦①♥ ♠♦ P②s tt ♦ ♣♣ r

❬❪ ♦r ♥ tr♦♥s ♦rt ♠♥t tr ♦ ♣♣ ②

Page 181: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P❨

❬❪ ❲ tr ♥♥♥ ♠♥t♦rsst♥ r♦♠ s②♠♠tr② tr♥ t♥ ♥ ♥♦♦② ♦ ♥ trs ♦ ♥♦ ♣

❬❪ ♠♠♦♥s ♥r③ ♦r♠ ♦r t tr t♥♥ t t♥s♠r tr♦s s♣rt ② t♥ ♥st♥ ♠ ♦r♥ ♦ ♣♣P②ss ♦ ♥♦ ♣♣

❬❪ ❲ r♥♠♥ ②♥s ♥ ♦ ♥♥♥ ♦♥t♥ ♦s②♠♠tr rrrs ♦r♥ ♦ ♣♣ P②ss ♦ ♥♦ ♣♣

❬❪ ❩ ♥ Pr ♥t t♥♥ ♥t♦♥s trs ♦② ♦ ♥♦ ♣♣

❬❪ ❲ ❩♦♥ r♥② ♥ ♦♠ trtr ♣r♦♣rts ♦ r②stsP②s ♦ ♣♣ ♥

❬❪ r ♥♥♥ t♥ rr♦♠♥t ♠s P②ss ttrs ♦ ♥♦ ♣♣

❬❪ ♦♥③s ♦♥t♥ ♥ ①♥ ♦♣♥ ♦ t♦ rr♦♠♥tss♣rt ② t♥♥♥ rrr P②s ♦ ♣♣ ♣r

❬❪ ❲ tr ❳ ❩♥ tss ♥ r♥ ♣♥♣♥♥t t♥♥♥ ♦♥t♥ ♦ Fe|MgO|Fe s♥s P②s ♦ ♣ ♥

❬❪ ❳ ❩♥ ❲ tr ♥ ♥②♦♣②② ts ♦ t r♦♥♦①②r ♥ ♦♠♦ t♥♥♥ ♥t♦♥s P②s ♦ ♣ ♣

❬❪ ❨ ❲♥ ❩♥ ❳ ❩♥ P ♥ ♥ ❳ ♥ rst♣r♥♣sst② ♦ ♠♦ s ♠♥t t♥♥ ♥t♦♥s t ♠ ♥tr②rs P②s ♦ ♣

❬❪ s♥ rt ♥ ♦♥t♥ ♥r ♥ ♣♥ t♥♥♥ ♣♥♦♠♥ ♥ s♥r②st ♠♥t t♥♥ ♥t♦♥ s②st♠s ♦r♥ ♦ P②ss ♦♥♥s ttr ♦ ♥♦ ♣

❬❪ P rs P r♦♣♦♦s ❲♥♥ P♣♥♦♦ ❱ ♥ ❩r ❱ r ♥ r♥♦s ♠♣♦rt♥ ♦ ♦♠♣① ♥ strtr ♥ rs♦♥♥t stts ♦r t♥♥♥ ♦r♥ ♦ ♥ts♠ ♥ ♥ttrs ♦ ♥♦ â⑨➇ ♣♣ ttt ♥tr♥t♦♥ ②♠♣♦s♠ ♦♥ t t②rstt

Page 182: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P❨

❬❪ ❱ ♥ ♦r② ♦ sr stts P②s ♦ ♣♣ ♥

❬❪ P r♦♣♦♦s P♣♥♦♦ ♥ P rs ♦♠♣① ♥ strtr ♥ t♥♥♥ tr♦ rr♦♠♥t /♥st♦r /rr♦♠♥t ♥t♦♥sP②s tt ♦ ♣♣

❬❪ r❱♥♥t s♥ ♦t ♥t ♥ ♦r P♦♣♦ ♥ ♦♥t♥ ♥ t♥♥ ♠♥t♦rsst♥ ♥ ♣t① ♠♦ t♥♥ ♥t♦♥s ♣♣ P②ss ttrs ♦ ♥♦ ♣♣

❬❪ ❩♥ P ② r② ♥ P Pr♥ ♥♥ ♦♠♥t♦rsst♥ ② ♦t tr♦♥s ♥ ♠♥t t♥♥ ♥t♦♥s P②s tt ♦ ♣♣ ♦

❬❪ s♥ r❱♥♥t ♦t ♥ ♦r ♦♥t♥ ♥r ♥ ♣♥ tr♥ ts ♥ ♠♦♥♦rst♥ ♠♦♠♥t t♥♥ ♥t♦♥s trs ♥ ♥ ♥♥r♥ ♦ ♥♦ â⑨➇ ♣♣ tt ②♠♣♦s♠ ♣♥tr♦♥stt

❬❪ P r② r Pr① ♥ ♥♦ ♥rr ♦♣t ♦♥st♥ts ♦ ♥st♦rs tr♠♥ ② rs♦t♦♥ tr♦♥♥r②♦ss s♣tr♦s♦♣② P②s ♦ ♣♣ ♣r

❬❪ ❱ r♦ ärs ♠ ♥ ü♥♥rr ♠♦rst ss ♥ ♦♠s ♥st tr♦♥ t♥♥♥ s♣tr ♦ ♠♦s ♠♥t t♥♥ ♥t♦♥s t r♥t tr♦ s♥sP②s ♦ ♣ ②

❬❪ ❩♥ ❳ ❩♥ ♥ ❳ ♥ ♣♥ ♦①s t❬s ❪ s♣♥tr rrr ♦r ss ♦ ♠♥t t♥♥ ♥t♦♥s ♣♣ P②ss ttrs♦ ♥♦ ♣

❬❪ trt t②♣ ♦ ♠♥t t♥♥ ♥t♦♥ s ♦♥ s♣♥ tr♥tr♦ r s②♠♠tr② ♦① ♦⑤♠♦⑤♦ ♥♦ ttrs ♦ ♥♦ ♣♣ P

❬❪ ♦♥ r rt♠② s ♠♦ ❱ ♥ rt♦ ❲♦rt♠♥♥ P ♥♦r qt ❱rs ♠rtP ♦♥t♦r ♦① ♥ P rs ❯s♥ ♠t♠♥♥t ♥trs t♦ r ♥sts ♥t♦ s♣♥tr♦♥s ♦r♥ ♦ P②ss♦♥♥s ttr ♦ ♥♦ ♣

Page 183: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P❨

❬❪ r ♠♦ P ♦♥t♦r ♥ ♦① ♥trs ♥ ♣t① tr♦strtrs ♦ ♣r♦st ♦①s P♦s♦♣ ③♥ ♦ ♥♦ ♣♣

❬❪ ♦♥ rtéé♠② ❱ ♥ s P ♥♦r qt P♦♥t♦r ♥ P rs srt♦♥ ♦ ♦r♥♦r♠ ♦ t♥♥♥r♦ss ♥ tr♦♥ t♥♥ ♥t♦♥ t♦ t♦t s②♠♠tr② tr♥ P②s ♦ ♣ ♣r

❬❪ ❱r rú♥ P♦st♠ ♦r ♥ ♥s♥ ♥♥♥♠♥t♦rsst♥ t ♣♦st ♥ ♥t s♥ ♥ la0.67sr0.33mno3/srtio3/Co♥t♦♥s P②s ♦ ♣

❬❪ s ♦♥ rt♠② ♥♥ ♦③♦♥ rrtr♦ qt P ♦♥t♦r ♥ r♥ r♦t ♥ rtr③t♦♥ ♦t♦❬s ❪ s rrr ♦r s♣♥♣♦r③ t♥♥♥ ♣♣ P②ss ttrs♦ ♥♦ ♣♣

❬❪ s ❲ ❨ ♥ ❯♥ ❨ ♥ ♥ ❨ ♦♦♥♦♣s t♦❬s ❪ ♠s ♣♦st ♦♥ srt♦❬s ❪ ② ♣s srt♦♥ ♦r♥ ♦ ♣♣ P②ss ♦ ♥♦ ♣♣

❬❪ ♥ rt③ rt ♠♥③ ♥ tr♦♠ ♥ ♣♦t♦tr♦♠ ♥stt♦♥ ♦ s♥r②st ♥ts♦r♥ ♦ t ♠r♥ ♠ ♦t② ♦ ♥♦ ♣♣

❬❪ s ❨ ❲ ♥♥stt ♥ r♠♥ tr♦♥ ♥ ♦♣t♣r♦♣rts ♦ ♥ts tio2 P②s ♦ ♣♣ r

❬❪ ❨s s♠ ♦t ❨ ③ ♥ ♥♦ ♥t t♥♥♥♠♥t♦rsst♥ ♣ t♦ ♣r♥ts t r♦♦♠ t♠♣rtr ♥ ② ♣t①♦♠♦♦ ♠♥t t♥♥ ♥t♦♥s t ♦ tr♦s ♣♣P②ss ttrs ♦ ♥♦ ♣

❬❪ ❳ ❩♥ ♥ ❲ tr r ♠♥t♦rsst♥ ♥ Co/MgO/Co♥ FeCo/MgO/FeCo t♥♥ ♥t♦♥s P②s ♦ ♣ ♦

❬❪ Pr♥ sr P♥ P s ♠♥t ♥ ❨♥ ♥t t♥♥♥ ♠♥t♦rsst♥ t r♦♦♠ t♠♣rtr t ♠♦ t♥♥ rrrs tr trs ♦ ♥♦ ♣♣ t ② s♥

Page 184: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P❨

❬❪ ♦♥ t ♥r rtr♥ P èr ♠s ♦♥t♥ ❲r♦t♦♥r♦s ♦♦ ♥ r♠ ♣♥♣♦r③ tr♦♥ t♥♥♥ ♥ FeCo/MgO/FeCo(001) ♠♥t t♥♥ ♥t♦♥s P②s tt ♦ ♣ ♣r

❬❪ ❨s t②♠ ♠ s♠ ♦t ❨ ③♥ ♥♦ ♥t t♥♥♥ ♠♥t♦rsst♥ ♥ ② ♣t① ♦②♥tr ♦♠♦ ♠♥t t♥♥ ♥t♦♥s ♣♣ P②ss ttrs♦ ♥♦ ♣

❬❪ ❲ ♦♥♥r ♦s ts ♥ rü rt s♦r♣t♦♥ ♥ ♠♥s♦♥ r♦ss♦r ♥ ♣t① ♦ ♠s P②s tt♦ ♣♣

❬❪ ❨s ❨ ③ t②♠ ♥ ♥♦ rtr③t♦♥ ♦ r♦t♥ r②st③t♦♥ ♣r♦sss ♥ ♦♠♦♦ ♠♥t t♥♥ ♥t♦♥strtr ② rt ♥r② tr♦♥ rt♦♥ ♣♣ P②ss ttrs ♦ ♥♦ ♣

❬❪ ❨ ♦ s♥ ❨ ♠♥ ♥ ②♣rr r♥s♠ss♦♥tr♦♥ ♠r♦s♦♣② st② ♦♥ t ♣♦②r②st♥ ♦♠♦♦ s ♠♥t t♥♥ ♥t♦♥ s♦♥ t♥♥♥ ♠♥t♦rsst♥ ♣rt ♥s♥ r②st ♠♥t t♥♥ ♥t♦♥ ♦r♥ ♦ ♣♣ P②ss ♦ ♥♦ ♣

❬❪ ③ ❨ ③ ♠ ♥ ❨s ♥ st s♥♥♥ t♥♥♥ ♠r♦s♦♣② ♦srt♦♥s ♦ ♣♦②r②st♥ ♠♦ t♥♥♥ rrrsr♦♥ ♦♥ ♠♦r♣♦s ♦ tr♦ ♣♣ P②ss ttrs ♦ ♥♦ ♣

❬❪ r s ♦r ♥ ♦r ❨ ♥♥ ♦♥t♥ ♦rt r ♥ s♥ ♠♦ t①tr t♥♥ ♥t♦♥s ①t♥ s♣♥ ♣♦r③t♦♥ trs ♦ s♥r②st ♥t♦♥s ♣♣ P②ss ttrs ♦ ♥♦ ♣

❬❪ rr ❨ ♦ ❨ r♠♦♥t ♠♥ ♥ Pt♦r♦♥ ♥♥ ♠♥t♦rsst♥ ♥ ♥tr② ♦①③ ♠♦s ♠♥t t♥♥ ♥t♦♥s t rr♦♠♥t ♦♦ ②rs ♣♣ P②ss ttrs ♦ ♥♦ ♣

❬❪ r♦♦t r P ♥♥ ♥ s♦ ss ♦ ♠trs ♠t rr♦♠♥ts P②s tt ♦ ♣♣ ♥

Page 185: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P❨

❬❪ ♦♠s tr♦♥ strtr ①♥ ♥ ♠♥ts♠ ♥ ♦①s ♥♣♥ tr♦♥s ❩s ♥ ♦r♥t♦♥ s ♦ ♦ tr ♦ts♥ P②ss ♣♣ ♣r♥r r♥ r

❬❪ ❩♥r ♥trt♦♥ t♥ t dss ♥ t tr♥st♦♥ ♠ts rr♦♠♥t ♦♠♣♦♥s ♦ ♠♥♥s t ♣r♦st strtr P②s ♦ ♣♣ ②

❬❪ s r ♥ r♠♥ r♠qt♦♣♦r♦♥r♦ss♦r ♦ ①♥ ♥ t ♣②ss ♦ ♦♦ss ♠♥t♦rsst♥P②s ♦ ♣♣

❬❪ P ❲ ♥rs♦♥ ♥ s ♦♥srt♦♥s ♦♥ ♦ ①♥ P②s ♦ ♣♣ t

❬❪ s P tt♦♦ ♥ r♠♥ ♦ ①♥ ♦♥♦s ♥♦t ①♣♥ t rsstt② ♦ La1−x

srxmno3 P②s tt ♦ ♣♣ ♥

❬❪ ♥ ♥ r tt② ♦ ♣♦②t♦♠ ♠♦s ♥ ♥rttr♦♥ stts ♦rt ♥r② Pr♦♥s ♦ t ♦② ♦t② ♦♦♥♦♥ rs t♠t ♥ P②s ♥s ♦ ♥♦ ♣♣

❬❪ P ♥♥s ts ♦ ♦ ①♥ ♥ ♠♥t r②sts P②s ♦ ♣♣ ♣r

❬❪ ♥ ♥ r♥ ♥ ♦♠s ♦ ①♥ ♥rt ♦rtsP②s tt ♦ ♣♣

❬❪ ❱ r s rtéé♠② ♦♥ qt P ♦♥t♦r♥ rt ♠♣rtr ♣♥♥ ♦ t ♥tr s♣♥ ♣♦r③t♦♥ ♦la2/3sr1/3mno3 P②s ♦ ♣

❬❪ Pr ❱s♦♦ ♠ ♦♥ ♠s ♥ ❱♥ts♥ ♥t ♣r♦♣rts t sr ♦♥r② ♦ ♠t rr♦♠♥tla0.7sr0.3mno3 P②s tt ♦ ♣♣

❬❪ s s ❱♥ ♦♥trt ❲♦ r②♥ ♦s ♥♦s ♠t♣s s♣rt♦♥ t la2/3ca1/3mno3/srtio3♥trs P②s tt ♦ ♣

❬❪ s ❱♥ s rt♥③ ♦♥trt ❲♦ ♦s ♥ r② r tr♣♣♥ ♥ ♦♣t♠② ♦♣ ♣t①♠♥♥t t♥ ♠s P②s ♦ ♣ t

Page 186: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P❨

❬❪ ró♥ r② ♥ ♥ r tr♦♥ strtr ♥♠♥t ♣r♦♣rts ♦ ♦♣ ♠♥♥ts P②s ♦ ♣♣ ♣

❬❪ ♠ ♠♦r ♥ ❨ ♦r t♥st♦r tr♥st♦♥s ♦ P②s ♦ ♣♣ t

❬❪ ❨ ❳ ♥ ♦ ①②♥♥②♥ s sttr♥ ♥Fe/MgO/Fe ♠♥t t♥♥ ♥t♦♥s P②s tt ♦ ♣ ♦

❬❪ rs♦ ♦tt② rrr ts ♥ t ♦♥t♥♠ ♦ ♣ stts P②s tt ♦ ♣♣

❬❪ ♥ ♦ ♥s♥ ♥ ♦♦r ♠♣rtr ♣♥♥ ♦ ♠♥t♦rsst♥ ♥ sr ♠♥t③t♦♥ ♥ rr♦♠♥t t♥♥♥t♦♥s P②s ♦ ♣♣

❬❪ ❨ r♥ rès P ♥♦r r♥♦t Ptr♦ ♦r é♣♥ ♦ ♥ é③éq ♣♥♣♦r③ ♥st t♥♥♥tr♦ ♥st♥ rrrs P②s tt ♦ ♣ ♣r

❬❪ ♦r②♠ ❲ ❲♥ ❳ ❩♥ ♥ ❳♦ ♥♥♥♠♥t♦rsst♥ ♥ ♦r♥t ♦♠♦♦ ♠♥t t♥♥♥ ♥t♦♥s r♦♥ ② s♣ttr♥ ♣♦st♦♥ ♣♣ P②ss ttrs ♦ ♥♦ ♣

❬❪ t♦♥ ♥ ❯♠rs ♦r② ♦ t♥♥♥ ♠♥t♦rsst♥ ♥ s♦rr Fe/MgO/Fe(001) ♥t♦♥ P②s ♦ ♣ t

❬❪ ❨ ♥ ♥ ♥ ♦② ♥ ♥r ♠♥t♦rsst♥♥ ♠♦ ♠♥t t♥♥ ♥t♦♥ s♥s♦rs s♥ t♦ ♣♥♥ ♦ tr♦s♣♣ P②ss ttrs ♦ ♥♦ ♣

❬❪ ♠r ♦s s r③rt ♦♠r Pr♥ ② ♥ ♥② r tr♣♣♥tr♣♣♥ ♠♥s♠ ♦ rrr r♦♥ ♥ ♠♦ ♠♥t t♥♥ ♥t♦♥s ♣♣ P②ss ttrs ♦ ♥♦ ♣

❬❪ ①r ❱♥tr P r♦ ♦s P r♥♥③rP ❲s♥♦s ♥ P P rts ♥ ♦ s♣♥♣♦r③ rt st t♥♥♥ ♥ ♦♥st ♦ s♣r♣r♠♥ts♠ ♥ ♠♦ ♠♥t t♥♥ ♥t♦♥sP②s ♦ ♣ ♣r

Page 187: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P❨

❬❪ ❲ ❲♥ ❳ ♦ ❲♥ ❳ ♥ P Prs♦♥ ♦r♥st ❳ ♦ ❨ P ❩♥ trrtt ♦ ♣ ♦♦r ♥ ❳♦ ❯♥rst♥♥ t♥♥♥ ♠♥t♦rsst♥r♥ tr♠ ♥♥♥ ♥ ♠♦s ♥t♦♥s t ♦ tr♦s P②s ♦ ♣ ♣r

❬❪ r♥♦s ♥ ♦♥t♥ s♥ ♦r ♥♦t s ♥♥ ♥♦ ♥ ♠♣t ♦ tr♦♥tr♦♥♥trt♦♥s ♥ ② s♦rr t ♥trs ♦♥ s♣♥♣♥♥t t♥♥♥♥ ♦♠♦♦ ♠♥t t♥♥ ♥t♦♥s P②s ♦ ♣

❬❪ ② ❨ tsr ♥ ♥♦ t♦ ♥♥♥ t♠♣rtr ♦♥ ♥t t♥♥ ♠♥t♦rsst♥ rt♦ ♦♦♠♦♦ ♠♥t t♥♥ ♥t♦♥s ♣♣ P②ss ttrs ♦ ♥♦ ♣

❬❪ ② ❨ ♥ tsr ♥ ♥♦♥♥ ♠♥t♦rsst♥ ♥ ♠♦rrr ♠♥t t♥♥ ♥t♦♥s t ♦ ♥ ♦ r ②rs ♦r♥ ♦ ♣♣ P②ss ♦ ♥♦ ♣

❬❪ ②♣rr s♥ r ❨♠t ❲t♥ ❨s ❨ ③ ♥ ♥♦ ♠♥t♦rsst♥ ♥♦♠♦♦ ♠♥t t♥♥ ♥t♦♥s ♣♣ P②ss ttrs ♦ ♥♦ ♣

❬❪ r ❨♠♠♦t♦ ③♥♠ ♥ ♥♦ ♥ ② tsr ♥ ♥♦ ♣r♣♥r♥s♦tr♦♣② ♦♠♦ ♠♥t t♥♥ ♥t♦♥ t tr ♦ ♣ ♣

❬❪ rr♥③ ♦♠③r rs r ss ♥ ♦ rq♥② ♥♦s t♦ ♠♥t ♥♦♠♦♥ts ♥ s♠r♦♥♦♠♦♦ ♠♥t t♥♥ ♥t♦♥s ♣♣ P②ss ttrs ♦ ♥♦ ♣

❬❪ ❲ ❲♥ ♠③ ❨ ❲♥ ❳ ♥ ♦r②♠ ♦ ❨❲♥ ❲ ❩♥ ♥ ❳♦ t♠ ♦t♦♥ ♦ t♥♥♥ ♠♥t♦rsst♥ r♥ ♥♥♥ ♥ ♦♠♦♦ ♠♥t t♥♥ ♥t♦♥s♣♣ P②ss ttrs ♦ ♥♦ ♣

❬❪ P ❩r♠tt♥ ♦♥ ♥r s s♥ ♥ ♥ ♥♥ ♦ ♦①②♥ ♠♦♥♦②r t ♠♦ ♥tr ♦♥ tr♥s

Page 188: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P❨

♣♦rt ♣r♦♣rts ♥ ♠♦ ♠♥t t♥♥ ♥t♦♥s ♣♣ P②ss①♣rss ♦ ♥♦ ♣

❬❪ ♦♥ ♥r t s♥ ♥ ♥♥ ♦♥sq♥s ♦ ♥tr ♦ ♦♥♥ ♥ s♦rr ♥ ♣t① ♠♦♠♥t t♥♥ ♥t♦♥s P②s ♦ ♣ ♥

❬❪ ❳ ♦ ❨ Pr ♦♦r t rs ♥ ü♥③♥r str♥ ♦ t♥♥♥ ♦r♥ ② ♦①②♥ ♥② ♥ ♣t①Fe/MgO/Fe ♠♥t t♥♥ ♥t♦♥s P②s tt ♦ ♣ ♥

❬❪ ❨s ♠ s♠ ❨ ③ ♥ ♥♦ ♥t r♦♦♠t♠♣rtr ♠♥t♦rsst♥ ♥ s♥r②st ♠♦ ♠♥t t♥♥♥t♦♥s t tr ♦ ♣

❬❪ t♦♠♦ r r③ ♥ ❨ ♥ rt r♠♦t♦♥♥ t♦♠s ♣r♦st tt♥t s♣rtts tr ♦ ♣ ♣

❬❪ ♦s♥tt ❲ ♦ P ❲♠s ❲♠s ♥ ❨ ♥♠♥s♥ ♦ ♥ F+ ♥trs ♥ ♠♥s♠ ♦① P②s ♦ ♣♣ ②

❬❪ ♣♣rs r♦s ♥ ♥s② F+ ♥ F′

♥trs ♥ ♠♥s♠ ♦① P②s ♦ ♣♣ ②

❬❪ ♦♠♥③r③ ♦s s ♥ P♦♥ r♦♥♥ ①tstt ♣r♦♣rts ♦ ♥tr ♦①②♥ ♥② rts ♥ t ♥ sr ♦ ♠♦ P②s ♦ ♣

❬❪ s♦♥ ②♦ ♥ P ♠♥ tt② ♦ ♥② ts ♥♠♦ r♦ ♦ r ♥trt② P②s ♦ ♣♣

❬❪ ♦♥ ♥ r♥r ♠rs♦ s♣tr♦s♦♣② ♦ t s ♠ss♦♥ ♥ ♥ str♦♥t♠ tt♥t P②s ♦ ♣♣ ♥

❬❪ s♦r♦é♥ ♥② ♥ ❩♥r t♦♠ ♦♥tr♦ ♦ ♦♥tt②rss rr♦♠♥ts♠ ♥ ♣ ♦①s st ♦♣♥ ❱ ♥ t ♥♥ts tio2 P②s tt ♦ ♣ ♥

❬❪ ❨ ❯♥ ♥ ❯♥♦ P♦t♦①tt♦♥ tr♣♣♥ ♥ r♦♠♥t♦♥ ♣r♦sss ♦ t f t②♣ ♥trs ♥ s♥ ♠♦ ♠r♦r②sts P②s ♦ ♣ ②

Page 189: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P❨

❬❪ ♥s P♦ts♥ ♥ ❨ ♥ ♣t ♣r♦♣rts ♦ ttts ♥ ❰♦ r ♥str♠♥ts ♥ t♦s ♥ P②ss srt♦♥ ♠ ♥trt♦♥s t trs ♥ t♦♠s ♦ ♥♦ â⑨➇♣♣

❬❪ ♣③③ ♥ r♦ ♣t ♣ ♦ str♦♥t♠ tt♥t t♦♥ r♦♠r t ♦r P②s tt ♦ ♣♣ ♦

❬❪ ♦ ♥ ❨ ♦ ♥ ❲ ♠ ♥ ♠ ♥♥ ♦ P♦t♦♠♥s♥ ♥ ② tr♠ ♥♥♥ ♥ srt♦❬s ❪t♥ ♠ ♣♣ P②ss ttrs ♦ ♥♦ ♣

❬❪ ♦♥ ♦ ♥ ♥ ♥ ①②♥♥② str♥ ♥ tr♦♥ ♦③t♦♥ ♥ ♦①②♥♥t srtio3 LDA+ust② P②s tt ♦ ♣ r

❬❪ ♥ rs♠ ♥ s♥♦ ♥ ♥ s③♠ ❨ ♥♠ts ❨ ♠ ♥ ♥♦ t ♠ss♦♥ t r♦♦♠ t♠♣rtr r♦♠ rrrt srt♦ t tr ♦ ♣ ♦

❬❪ r♥r P♦t♦♠♥s♥ ♥ srto3 P②s ♦ ♣♣ ♥

❬❪ ❩s ♦♣t♦ r ♥t Pt♥ts ♦♥ ♥♥r♥ ♦ ♥♦ ♣♣

❬❪ ♣♣♥s rtr♥sr s♣tr ♦ tr♥st♦♥♠t ♦♥s ♥ ♦r♥♠P②s ♦ ♣♣ ♥

❬❪ ♥♠r ♠♣s② ss r♥ ♥ rr♦s s♦♥ ♦①t♦♥ ♥ rt♦♥ t t ♦♠♦ ♥tr st ② s♦t ①r② s♦r♣t♦♥ s♣tr♦s♦♣② ♥ ♠♥t rrr♦s♠ ♣♣ P②ss ttrs ♦ ♥♦ ♣

❬❪ ❲st ♥ st ♥♦♦ ♦ ♠str② ♥ P②ss t Prss ♦ t♦♥

❬❪ rt♦♥ s ❨ s②♠ r②s♦ ♥ ♥♦♥♥t♦♠ ♥ tr♦♥ strtr ♦ t ♦♠♦ ♥tr r♦♠ rst ♣r♥♣s ♣♣ P②ss ttrs ♦ ♥♦ ♣

❬❪ ❲ ♦ P ❨ ♥ ❲ s♥ ❨ r♠♥ ♥ r t♦♠s s♣tr♦s♦♣ ♠♥ ♦ ♦♠♦♦ ♠♥t t♥♥ ♥t♦♥s ♣♣ P②ss ttrs ♦ ♥♦ ♣

Page 190: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P❨

❬❪ ❨ ♥ ♥ ♦ ♥ ♥ ♦♥ t ♦ s r♥♥♥♥ ♦♥ t tr♦♥ strtr ♦ t ♠♦ rrr ♥ ♦♠♦♦♠♥t t♥♥ ♥t♦♥s ♣♣ P②ss ①♣rss ♦ ♥♦ ♣

❬❪ ❱ rt ❨ s ♦ ♦♥♦ ♥ ♥♦r♥s♠ss♦♥ tr♦♥ ♠r♦s♦♣② ♥stt♦♥ ♦ ♦♠♦♦ ♣s♦s♣♥ s ♥♥ t r♥t t♠♣rtrs ♦r♥ ♦ ♣♣ P②ss♦ ♥♦ ♣

❬❪ rs♦♥ rqs P Pr♦s sr ❨♥ ♥ Pr♥♥♥s s♦♥ ♥ ♥♥ ♠♥t t♥♥ ♥t♦♥s t ♠♦ t♥♥rrrs r♣t tr ♦ ♥♦ ♣♣

❬❪ ♥ ❨ s②♠ ♥ Ptt♦r t♦♠ ♥ tr♦♥strtr ♦ Co/srtio3/Co ♠♥t t♥♥ ♥t♦♥s P②s ♦ ♣

❬❪ r③r ♥s♦r ♥ rs rr♦tr t ♦♣③rt♦❬s ❪ t♥ ♠s ♠sr ♥ t♠♦s♣rs ♦ r②♥ ♦①②♥ ♦♥♥trt♦♥ ♣♣ P②ss ttrs ♦ ♥♦ ♣♣

❬❪ tr♦ ♥r trt ♥ ❲♠s ♠ss♥♠♠rst♦r ♦♥ tr ♦ ♣ ②

❬❪ ♦♥ r rt♠② P Pr♦♦♠♠ qt P♦♥t♦r ♠♦ ♥ ♦① srt ♠♥t t♥♥ ♥t♦♥st st s♣♥♣♥♥t stts ♣♣ P②ss ttrs ♦ ♥♦ ♣

❬❪ ♥t ♥ r♠ tr♦♥ strtr ♦ tr♦♥ ♦♣ srtio3srtio3−δ ♥ sr1−xlaxtio3 P②s ♦ ♣♣ ♥

❬❪ ❨ ❲t♥ ♥♦r③ ts rr ❲♠r ♥ ❲♥ rr♥tr♥ ♥st♦r♦♥t♦r tr♥st♦♥ ♥ ♥♦♥♦t♠♠♦r② ♥ r♦♠♠♦♣ srt♦❬s ❪ s♥ r②sts ♣♣ P②ss ttrs ♦ ♥♦ ♣♣

❬❪ sst st♥ ♥ tr♥st♦♥ ♠t ♦①s trs ♦②♦ ♥♦ ♣♣

❬❪ rt♥ ② ❨ ♥r② r ♦♥ ❱ ♦st rs ♥ ♦♥ ♥♦♠ rrr ♦ ♠♦ ♦rrsst st♥ ♥ t♥♥ rrrs ♦r♥ ♦ ♣♣ P②ss ♦ ♥♦ ♣

Page 191: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P❨

❬❪ ② ♦♥ r ❨ ♥r② ❯q♦t❲ ❲r rt♦♥ ❱r ♥ ❱ ♥♦♦ tr st♥♥ r♠♦ ♠♥t t♥♥ ♥t♦♥s ♣♣ P②ss ttrs ♦ ♥♦ ♣

❬❪ r ② ♦♥ ❨ ♥r② ♥ ♦♥tr st♥ ♥ ♠♦ t♥♥ ♥t♦♥s P②s ♦ ♣ ②

❬❪ rr t♥ t ♥ ♠♥t t♥♥ ♥t♦♥s s ♦♥ ♠♦P tss

❬❪ ♠r ❨ ❨♠ ♦②♦s s ♦♥♠ ♥ s ①♣♦rt♦♥ ♦ ♦①s t ♠♥t s♠♦♥t♦rst♦r tr♥s♣r♥t s♣♥tr♦♥s ♣♣ r ♥ ♦ ♥♦ â⑨➇♣♣ ttPr♦♥s ♦ t ♦♥ ♣♥❯ ❲♦rs♦♣♦♥ ♦♠♥t♦r trs ♥ ♥ ♥♦♦②tt

❬❪ t t♥②r ♣rs♣t ♦♥ t ♠♥t s♠♦♥t♦rs ♥ ♦①s t tr ♦ ♣♣

❬❪ ❨ ts♠♦t♦ r♠ ♦♥♦ s ♠r s P ♠t ②♦ ② ♦sr ♥ ♦♥♠♦♦♠t♠♣rtr rr♦♠♥ts♠ ♥ tr♥s♣r♥t tr♥st♦♥ ♠t♦♣ tt♥♠ ♦① ♥ ♦ ♥♦ ♣♣

❬❪ rt♥③♦t rt♥③ r♥♥③ P Pr♥♦ ♥t♦♥② rt♦♠ s ❩ ♦♥st♥t♥♦ ♥ rt♥③ ♠♥s♥ t r♦♦♠ t♠♣rtr ♥ t ♠♦ ♠s ♦ tt ♦♠♠♥t♦♥s ♦ ♥♦ ♣♣

❬❪ rt♥③♦t tr♥ s ❩ ♦♥st♥t♥♦ ❱♥ ♠t③ r♦ str ♦r♥ ♥ rt♥③ rr♦♠♥ts♠♥ tr♥s♣r♥t t♥ ♠s ♦ ♠♦ P②s ♦ ♣

❬❪ ♠♥ ♦♠♦ ♥ r♣r ♥♦♦② ♥ ♣♣t♦♥s ♦ r♦♠ ♦♥ s♦rs s ♥ s♣ttr♥ ♣rt ♦♥ s♦r t♥♦♦② ♦r♥ ♦ ❱♠ ♥ ♥ ♥♦♦② ♦ ♥♦ ♣♣

❬❪ ♠ rs ❱ ♦st ♠rr ♦♥ ♦r ♥ r♣r ♥♥ ♦ ♥ st ♥♥♥ ♦♥ t ♥♥♦s t♦♣♦r♣tr ♣r♦♣rts ♦ t t♥♥ rrr ♥ s♣ttr ♣t① ♠♦♠t②rs ♦r♥ ♦ P②ss ♣♣ P②ss ♦ ♥♦ ♣

Page 192: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P❨

❬❪ ❲♦r ♥ ♣♥♣♦r③ t♥♥♥ ♥ ❬s❪sr❬s ❪♠♥♦❬s ❪ ♣♣ P②ss ttrs ♦ ♥♦ ♣♣

❬❪ Prs♥ ♥ ❱r♥♦♥ t ♦ ♠ rsst♥ ♦♥ ♦♠♣♥t♥♥♥ ♠sr♠♥ts ♣♣ P②ss ttrs ♦ ♥♦ ♣♣

❬❪ ♥ ♥ ♥♥s r tr♦♥ ♥rs ♦ t ♦tr s tr♦♥sr ♥ ♦ ♥♦ ♣♣

❬❪ P ♦ttä♥r ♥ ♥ tr♠♥♥ t ♥tr rrrt ♥ ts rt♦♥ t♦ t♥♥ ♠♥t♦rsst♥ P②s ♦ ♣ ♥

❬❪ P ❱ s♥♦ trt ♥ r s ♥ ❨ s②♠ t s♣♥ ♣♦r③t♦♥ ♥ r t♥♥♥♠♥t♦rsst♥ ♥ ♣t① Co|srtio3|Co ♠♥t t♥♥ ♥t♦♥s P②s tt ♦ ♣ ♦

❬❪ ttss t ♦ t ♣s tr♥st♦♥ ♦♥ t srto3 ♦♥t♦♥♥s P②s ♦ ♣♣

❬❪ ♦③ sr♦ ♥ ♥♠ P♦t♦♠♥s♥ ♥ rrs♣♦t♦♥ s♣tr ♥ ♦ srt♦ ♦r♥ ♦ P②ss ♦♥♥s ttr ♦ ♥♦ ♣

❬❪ ♦ ♦s r r ❱rs♥ rr ❯q♦t ♠rr ♦♥ ♥ ♥ t ♦ ♥tr ♦♥♥ ♦♥ t tr♥s♣♦rt ♣r♦♣rts ♥ ♦2/srt♦3/♦2/ ♠♥tt♥♥ ♥t♦♥s P②s ♦ ♣

❬❪ ♦♥ ①♣r♠♥t ♥sts ♥t♦ s♣♥♣♦r③ s♦ stt t♥♥♥P tss

❬❪ ❨ s②♠ ♥ Ptt♦r ♣♥♣♦r③ tr♦♥ t♥♥♥ r♦ss s♦rr ♥st♦r P②s ♦ ♣♣

❬❪ ❨ s②♠ ♦♦♦ r♥♦ ♥ ♦♥ s♦♥♥t ♥rs♦♥ ♦ t♥♥♥ ♠♥t♦rsst♥ P②s tt ♦ ♣ ②

❬❪ ♠ ❲ ♦ r ♥ ♦r ❱ s♥ r rs ♠rr r♣r ❲ ♦ ♥ ♦♥♦♥tr♦ ♦ t♠t t♥♥♥ rrr ts ♥ trt♥ ♠♦ ♠s♣♣ P②ss ttrs ♦ ♥♦ ♣

Page 193: Impact of structural defects on spin-polarized transport ... · Impact of structural defects on spin-polarized transport across magnetic tunnel junctions par FILIP SCHLEICHER Soutenue

P❨

❬❪ s ♥ P♦♥ ♣t ♣r♦♣rts ♦ sr ♥ ♥trs♥ ♠♦ r♦♠ ♥t♦ str ♠♦ t♦♥s ♦r♥ ♦ ♠P②ss ♦ ♥♦ ♣♣

❬❪ ❨ ♥ ❲♠s ♥ ❲ ② t str ♥trs ♥ ♠♦P②s ♦ ♣♣ ♥

❬❪ P ♦♥r ♥ rt♠♥ ♥ s♦r♣t♦♥ ♥s ♥ ♠♦ r②stsP②s ♦ ♣♣ ♣

❬❪ r♦ r ♥ts ♥ q♥t♠ t♥♥♥ P r♦♣②ss ttrs♦ ♥♦ ♣

❬❪ ①r ❱♥tr P r♦ ♦s P ❲s♥♦s r♦s♦ ♥ P P rts s♦♥♥t t♥♥♥ tr♦ tr♦♥ tr♣♣♥ stts♥ t♥ ♠♦ ♠♥t ♥t♦♥s P②s tt ♦ ♣ ②

❬❪ rt s♥ ♦♥t♥ ♥ ② ♥♦♥ ♦♥ ♥ ❲ ❲r ♥ ♦ s②♠♠tr②♣♥♥t ♠t rrr ♥ ② ♣t① ♠♦ s ♠♥t t♥♥ ♥t♦♥s P②s tt♦ ♣ ♦