1 35 YEARS OF METALLIC SUPERLATTICES DOE NSF, AFOSR, ONR IVAN K. SCHULLER IEEE DISTINGUISHED LECTURER
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35 YEARS OF METALLIC SUPERLATTICES
DOENSF, AFOSR, ONR
IVAN K. SCHULLER
IEEE DISTINGUISHED LECTURER
IEEE Magnetics Society Home Page: www.ieeemagnetics.org– 3000 full members– 300 student members
The Society– Conference organization (INTERMAG, MMM, TMRC, etc.)– Student support for conferences– Large conference discounts for members– Graduate Student Summer Schools– Local chapter activities– Distinguished lectures
IEEE Transactions on Magnetics– ~2000 peer reviewed pages each year– Electronic access to all IEEE Transactions on Magnetics papers
Online applications for IEEE membership: www.ieee.org/join– 360,000 members – IEEE student membership IEEE full membership
The Journal of Your Field
On line at ieeexplore.ieee.orgSubmit manuscripts at mc.manuscriptcentral.com/maglet‐ieee
Peer reviewed
Rapid publication
Worldwide circulation
IEEE Xplore archive
Four‐page articles
No page charges
4
Thank you
What WE thinkof Science
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•Boooooooooring !!!!!!!•That Is The Subject I Never Understood
In High School (College)•You Must Be Very Intelligent
What the rest of the world thinks
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8
Bangs
Small Bangs
Big Bangs
MOST DON’T DO THIS
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FASCINATING PHYSICSUSEFUL
YOU USE IT MILLIONS OF TIMES A DAY
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WHY PHYSICS
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My Start58 YEARS AGO
1957
Cluj, Kolozsvar, Clausenburg
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Lucky to Live in Chile
“Life need not be easy, provided only that it is not empty.”
Lise Meitner
Danny, Oceanographer
Jonny, Physicist
Jackie,Teacher
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Lucky to Study in Chile
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SOMETHING FROM NOTHING
• Noether’s theoremConservation laws from philosophy
• Ginzburg-Landau 2nd order phase transitionSuperconductivity, magnetism …………………….
from series expansion
Ask fundamental questions
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SYMMETRY
AND
CONSERVATION LAWS
Emmy Noether
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Landau-Ginzburg
TAYLOR EXPANSION
Order Parameter: Superconducting Gap, Magnetization, Distorsion,
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18
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CRITICAL SLOWING DOWN
TEMPERATURE
Rel
axat
ion
Tim
e (n
sec)
I. K. Schuller and K. E. Gray, PRL36, 429(1976)
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Many Young Friends
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Why do Physics
• Universal behaviorPower Laws
• New Parameters RangeSmaller
• Weird BehaviorSeparate Charge and Spin
• Big QuestionsWhat is intelligence
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Why do Physics
• Universal behaviorPower Laws
• New Parameters RangeSmaller
• Weird BehaviorSeparate Charge and Spin
• Big QuestionsWhat is intelligence
24Z. Yang, C. Ko, and S. Ramanathan, Annu. Rev. Mater. Res. 41 (2011)
Metal-Insulator Transition
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VO2
25338 339 340 341 342102
103
104
R (
)
T (K)
310 320 330 340 350 360101
102
103
104
R (
)
T (K)
339 340 341 342
2
4
6
R (k
)
T (K)
200 nm
Multiple jumps across the metal-
insulator transition
Nano-scale VO2R
2626
Scale Invariance
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101 102 103
100
101
102
103
104
Num
ber o
f Jum
ps
Jump size ()
100 cycles
Statistics of Jumps
Power law: p(A) A-
p-probability A- jump size
40 80 1200
500
1000
1500
2000
Num
ber o
f Jum
ps
Jump Size ( = 2.480.05
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Avalanches
• Triggered and develops
• Many Small avalanches
• A few big ones
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UNIVERSALITY OF
PHYSICS
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Power Laws
M. Newman Phys. Today, P. 33 Nov. 2008
Earthquake Magnitude
Connectivity of InternetJP. Sethna et al., Nature 410, 242 (2001)
Citations (I.K. Schuller)
= 1.2
= 2.1
10 100 1000
1
10
100
Num
ber o
f Pap
ers
Number of Citations
= 1.7
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~1.3
Sand Piles
Avalanches with Power Laws Plasma Burst (sun)
Martensites
~2.4
Barkhausen Noise
~1 - 3, depends on sand
~2.0
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Why do Physics• Universal behavior
Power Laws
• New Parameters RangeSmaller
• Weird BehaviorSeparate Charge and Spin
• Big QuestionsWhat is intelligence
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Nanoscience
PhysicsChemistry
CHARACTERISTIC LENGTH SCALES
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Un homme de six pieds faitsur la terre la meme figureprecisement que fait sur uneboule de quatre pieds de circonference un animal quiserait a cette circonference de roue comme 1 est a 91 500 000
Merci Andre MagnanPresident Soc. VoltaireKVAB, U. de Nanterre
NanoBioFrench Theorist
~10nm
NANO VOLT
Francois-Marie Arouet
NANO VOLTAIRE
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SCIENCE DRIVEN RESEARCH
I.K.Schuller, Phys.Rev.Lett. 44, 1597(1980)
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MAGNETO-TRANSPORT
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~ 20 % MR
Giant MagnetoResistance- GMR
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April, 1981
In 4 or 5 years, this will be THE fieldin materials science.
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2007 PHYSICS NOBELGrunberg Fert
GIANT MAGNETORESISTANCE
GMR
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U C T )
T E
AP
PL
ICA
TIO
NS
Hard disk drives
MRAM
Sensors
SC
IEN
CE
Co
Cu
I
State: +1
State: 0
State: -1
-4 -3 -2 -1 0 1 2 3 4
-1
0
1 HFC (kOe) 0.5 2.0 5.0
M /
MS
H (kOe)
GMR SPIN TORQUE
EXCHANGEBIAS
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Nanoscience(when things get small)
TunnelSchroedv8_1-desktop.m4v
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e-
charge
electronics
magnetism
electron
Spin-electronicsor
Spintronics
spin
44Basic Research=Transformative Technology
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Why do Physics• Universal behavior
Power Laws
• New Parameters RangeSmaller
• Weird BehaviorSeparate Charge and Spin
• Big QuestionsWhat is intelligence
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THE REALCHESHIRE CAT
Went away and left behind his smile
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FM FM
NM
I
V
NON-LOCAL SPIN VALVE
FM: ferromagnetic
NM: non-magnetic
Decouple
SPIN current from CHARGE current
I
A Crazy experiment
Valenzuela et al.,PRL 94, 196601 (2005)
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Sample
0.5µm
1µm
FM
NM
FM
Photolithography + Au contacts
Py/Cu/Py Co/Al/Co
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-800 -600 -400 -200 0 200 400 600 800-1.0
-0.8
-0.6
-0.4
-0.2
0.0
0.2
0.4
0.6
0.8
1.0I=0.5 mA
T=4.2 KPy/Cu/Py
V/|I
|(m
)
H (Oe)
-800 -600 -400 -200 0 200 400 600 800-1.0
-0.8
-0.6
-0.4
-0.2
0.0
0.2
0.4
0.6
0.8
1.0I=0.5 mA
T=4.2 KPy/Cu/Py
V/|I
|(m
)
H (Oe)
-800 -600 -400 -200 0 200 400 600 800-1.0
-0.8
-0.6
-0.4
-0.2
0.0
0.2
0.4
0.6
0.8
1.0I=0.5 mA
T=4.2 KPy/Cu/Py
V/|I
|(m
)
H (Oe)
-800 -600 -400 -200 0 200 400 600 800-1.0
-0.8
-0.6
-0.4
-0.2
0.0
0.2
0.4
0.6
0.8
1.0I=0.5 mA
T=4.2 KPy/Cu/Py
V/|I
|(m
)
H (Oe)
Non-local spin valve effect
•Bipolar switching
• Spin signal:
IVV
IV APP
•Memory effect
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Magnetic RAM4 Mbit chip
Revisited: 1995Demo: Motorola 2003
Market: Freescale 2006
Magnetoresistive read headDiscovery: 1988
Market: IBM 1997
Spintronics: applicationsGiant magnetoresistance (GMR)
Tunnel magnetoresistance (TMR)
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Why do Physics• Universal behavior
Power Laws
• New Parameters RangeSmaller
• Weird BehaviorSeparate Charge and Spin
• Big QuestionsWhat is intelligence
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11,968 processors, 12 Terabytes memory,
600 Terabytes disk storage
Jonathan Schuller6 months old
$ 200,000,000$ 30,000
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Unifying Principlesfor
Intelligence ?Imitate Nature
“Biologically Inspired”
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CENTRALPROCESSOR
Local processor
Local processor
Sensors Sensors
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CENTRALPROCESSOR
SensorsSensorsLocal
processorLocal
processor
Nanoscience
CommunicationsFeedback
Wireless
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IMPLEMENTATION
Reduce to practiceImitate nature
FUNDING
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What is needed
• Expertise- physicists, chemists, biologists, engineers• Techniques-Nanoscience, Materials, Wireless,Engineering• High Tech Facilities• Various implementations• Interactions• Steady Support
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Organic Thin FilmsStructure, Transport, SELECTIVE Sensing
Work supported by AFOSR-MURI
PhysicsCorneliu N. Colesniuc, Amos Sharoni, Casey W. Miller, Ge Liu,
Chemistry,Richard D. Yang, Forest Bohrer ,Andy C. Kummel, William Trogler,
EngineeringJeongwon Park
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Metallo Phthalocyanine – M C32N8H16
C
N
M = Cu, Fe, Ni, Co, ....or 2H
H
Model System for Planar Organics
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Organic Molecular Beam Epitaxy (OMBE)
substrate
Substrate TemperatureT=30oC – 250oC
phthalocyanine
Phthalocyanine sublimes near 400oC
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200 400 600
0.8
1.0
nor
mal
ized
cur
rent
Time (min)
small grains (25 C)m
etha
nol
met
hano
l
dosage
Bluetooth RX/TX
ChemFETMicrocontroller
Gain Amplifier
Temp & Humidity
Chemical SensorsChange Resistance
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DISRUPTIVE TECHNOLOGY
ARISES UNEXPECTEDLY FROM
REVOLUTIONARY BASIC SCIENCE
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SUMMARYDo what you like,
but above all like what you do
Francisco SchullerParaphrasingLise Meitner
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Enjoy the Process
•Caminante no hay camino, se hace el camino al andar.
Antonio Cipriano José María y Francisco de Santa Ana Machado y Ruiz
(26 July 1875 – 22 February 1939)
•Wanderer, there is no road,the road is made by walking.
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This is Why Why DoPhysics ?
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FUTURE