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Coherent VUV generation :Coherent VUV generation :High order Harmonics in gases (High order Harmonics in gases (160 - 10nm)160 - 10nm)
EnergyUVX Electronic trajectory in the laser field
Proof of semi-classical three-step model
Attosecond time structure and dynamicsAttosecond time structure and dynamics
Energy / Peak powerEnergy / Peak power
160 120 80 70 60 50 40 30 20 10nJ
10nJ
100nJ
µJ
10µJ
100kW
MW
10MW
100MW
1GWRiken 16mJ
Xe
Saclay : EL= 20-25mJ
Hannover: KrF 14mJ 500fsE
nerg
y / p
ulse
(nm)
Pe
ak P
ow
er (2
0fs X
UV
pu
lse)
Ne
Ar
Riken 130mJ
Riken 16mJ
Scaling laser energy and medium at constant IL (Laserlab I3 ) 10µJ
7 9 11 13 15 17 19 21 23 250
10
20
30
40
50
60
70
80
90
100
Ref
lect
ivity
of
two
SiO
2 P
late
s at
10°
Harmonic order
7 9 11 13 15 17 19 21 23 25 27 29
0
20
40
60
80
100
Measured T thickness : 100nm 160nm
Filt
er
Tra
nsm
issi
on
(%
)
Harm order
CXRO data 100nm 160nm
Spectral selection
• Silica plates + metallic filters
• Grating time stretch
• Multilayer mirrors (< 40 nm)
RIR ~ 10-4
Al
10 15 20 25 30
0,00
0,05
0,10
0,15
0,20
0,25
0,30
0,35
0,40
0,45
0,507 9 11 13 15 17 19
Tra
nsm
issi
on
Photon energy (eV)
In 162nm (CXRO) Sn 162nmIn, Sn
= 0.5 :
Coherent flux ~ 75% Total flux
d=1mm
d=2mm
d=3mm
H13 (15)61nm
Fresnel bi-mirror Interferometer
Le Déroff et al. PRA 61 (2000) 043802
0,2 0,4 0,6 0,8 1,00,0
0,5
1,0
= 61.5 nm (H13)
Cohere
nt F
lux / T
ota
l F
lux
Coherence degree
Spatial Coherence of High HarmonicsCollab. Lab. Charles Fabry Orsay
Focussing
0
5
10
15
200 400 600 800 10000
2
4
6
M2
Backing Pressure (torr)
H15 (52 nm)
w0 (
µm
)
f=200 mm
• Multilayer spherical M
• Bragg Fresnel lens (Mo/Si)
1µJ at 20eV : IUVX ~ 1014 W.cm-
2
2.5 µm
• Parabola f=70mm
Zeitoun et al. LOA-LIXAM-20 -10 0 10 20
2
4
6
8 H37 (21.6 nm)
Spo
t dia
met
er (
µm
)
Distance to focus (µm)
f=50mm
Spatial interferometry
Spectral interferometry
Mutually coherent harmonic sources
80µm 180µm 380µm 600µmx=
H17
-5 -3 -1 1 3 50,0
0,2
0,4
0,6
0,8
1,0
H11
(Å)
t=150fs
Inte
nsity
-3 -1 1 3 5 (Å)
t=450fs
x
t
Separated spatially
Separated temporally
Frequency modulation :
Temporal properties
50 45 40 35 30 25
0,00
0,05
0,10
0,15
0,20
0,25
Ar25
XU
V I
nte
nsi
ty (
arb
. u
nits
)
(nm)
~10-3 -10-2
Coherence time < pulse duration
t
Iq
tL
Lq
Reconstruction of E() and from the
spectral interference pattern
2 Replicas
•Temporal delay
•Spectral shift
²)(²)()( EES
))()(cos()()(2 EE
Grating
Spectral interference
C. Iaconis & I.A. Walmsley, Optics Letters 23 (1998)
Complete characterization of an XUV pulsePrinciple of SPIDER in the visible
F. Verluise et al., Optics Letters 25 (2000)
DAZZLERLaserOscillator
Acousto-optic filter Tailoring of the IR pulse
GasJet
Lens
HH Generato
r
Creation of two delayed replicas is programmable and accurately set by the Dazzler
Spectral shift of one of them set by cutting the wings of the laser spectrum
q
q
HHG Transfer as =q.on harmonic q is measured on the harmonic spectra
Transposition in XUV : “Dazzling SPIDER”
Amplifier
Mairesse et al. PRL 2005
Quadratic spectral phase
Quadratic XUV temporal phase (IL-dependent)
Negative linear chirp : q = qL + bq t
SPIDER XUV SPECTRUM In
tens
ity (
a.u.
)
25,6 25,7 25,8 25,9 26,0 26,1 26,28
9
10
11
Inte
nsity
.10-15 rad/s
Phase (rad)
SPIDERALGORITHM
Phase-locked XUV pulses
Chirp Rate b11= 1.2 10 28 s-2
Complete characterization of harmonic pulse
-100 -50 0 50 100228
229
230
231
232
233
234
235
236
IR XUV (H11)
Inte
nsity
Time (fs)
XUV Phase (rad)
Temporal profile of harmonic emission
FWHM=50fsFWHM=22fs Consistent
Varju et al., JMO 52, 379 (2005)
13 15 17 19 21 23-3
-2
-1
0
1x1028
Chi
rp ra
te b
q (s
-2)
Order
Exp. bfund
=0 Th.
Exp. bfund
=0.8 1027 s-2
Th.
HHG cellToroidal Mirror
Delay line
1 J, 30 fs10Hz
Kr plasma
Al Filter
20 mJ, 30 fs
/4
towards diagnostics
Ph. Zeitoun et al., Nature 431, 426 (2004)
Amplification of harmonics in a laser medium
3d94d J=0
Ni-like Kr 8+ : (Ne)3s23p63d10
Collisions
e - ions3d94p J=1
32,6nm
0
2000
4000
6000
8000
10000
12000
0 100 200 300 400 500 600 700 800
XRL line
0
2000
4000
6000
8000
10000
12000
0 100 200 300 400 500 600 700 800
HHG +XRLnon synchronized
0
2000
4000
6000
8000
10000
12000
0 100 200 300 400 500 600 700 800
Amplified harmonic
Amplification in Krypton IX plasma at 32.8 nm
Harmonic 25 alone Amplified Harmonic
Amplification Factor : 15 à 200 (depending on seed level) Divergence : < 2 mrad
Prints of Laser at 32.8 nm
Amplification of harmonics in X-Ray laser : TUIXS (NEST)
L’amplification dépend du niveau d’injection
Gss = 80 cm-1
Iseed ~ Isat/100 : strong amplification (x 200)
Iseed ~ 4Isat : moderate amplification ( x 20)
Broad band Amplification > ASE regime
Attophysics group 2005Attophysics group 2005P. Breger H. Wabnitz PDocB. Carré W. Boutu PhDM.-E. Couprie M. de Grazia PhDH. MerdjiM. Labat PhDP. Monchicourt G. Lambert PhDP. Salière s Y. Mairesse PhD
ContractsContracts
I3 Laserlab : access (SLIC) / Development of Coherent ultra-short XUV source Applications of Coherent ultra-short XUV : Marie Curie RTN “XTRA” Amplification of harmonics in X-Ray laser : TUIXS (NEST) Seeding of FEL with laser harmonics generated in gas : EUROFEL-DS4
CollaborationsCollaborationsLab. Francis Perrin, CEA-SaclayLab. Francis Perrin, CEA-Saclay
Salières et al. PRL (1999)Descamps et al. Optics Lett. (2000)
Interferogram in virtual Object plane
IR beam splitter
In 2001-2005 Multi-photon/multi-color photoionization of atoms (AMOLF 2003)
Photoionization of water in the liquid phase (Univ. Stockholm 2004) Surface ablation by XUV pulses (Univ. Warsaw, PALS 2005) Photoionization of clusters by XUV pulses (Technische Univ. Berlin 2005)
High intensity in the XUV (~ 1012W/cm2) : Non Linear processes Short duration (10fs100as) /synchronization with laser : time-resolved studies Intrinsic or mutual coherence : interferometry techniquesAtomic physics (photoionization): Toma et al. Phys. Rev. A (2000).
Solid state physics : Quéré et al., Phys. Rev. B (2000), Gaudin et al., Appl. Phys. B (2004)
Plasma physics : Salières et al., Phys. Rev. Lett. (1999), Descamps et al., Opt. Lett. (2000).
Applications of Coherent XUV pulses
7 9 11 13 15 17 19 21 23 25
0
10
20
30
40
50
60
70
80
90
100
Ref
lect
ivity
of
two
SiO
2 P
late
s at
10°
Harmonic order
7 9 11 13 15 17 19 21 23 25 27 29
0
20
40
60
80
100
Measured T thickness : 100nm 160nm
Filt
er
Tra
nsm
issi
on
(%
)
Harm order
CXRO data 100nm 160nm
Spectral selection
10 15 20 25 30
0,00
0,05
0,10
0,15
0,20
0,25
0,30
0,35
0,40
0,45
0,507 9 11 13 15 17 19
Tra
nsm
issi
on
Photon energy (eV)
In 162nm (CXRO) Sn 162nm
5 10 15 20 250
10
20
30
40
50
60
70
80
90
100
Polarization S
Tr
/ Re
(%)
Incidence (°)
Transmission Reflectivity
• Silica plates + metallic filters
• Grating time stretch
25 30 35 40
0,00
0,05
0,10
0,15
0,20
0,25
0,30
0,35
B4C/Si
Ref
lect
ivity
Wavelength (nm)
Simul (inc=4°) Exp:
, incidence 4°, 5°
Spectral selection and focussing
0
5
10
15
200 400 600 800 10000
2
4
6
M2
Backing Pressure (torr)
H15 (52 nm)
w0 (
µm
)
Spherical Mirrorf=200 mm
• Multilayer mirror (< 40 nm)
• Bragg Fresnel lens (Mo/Si)
1µJ at 20eV : IUVX ~ 1014 W.cm-
2
2.5 µm
Parabola f=70mm
Zeitoun et al. LOA-LIXAM
Reconstruction of from the
spectral interference pattern
2 Replicas
•Temporal delay
•Spectral shift
²)()( ES
²)( E
))()(cos()()(2 EE
Grating
Spectral interference
C. Iaconis & I.A. Walmsley, Optics Letters 23 (1998)