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Coherent VUV generation : High order Harmonics in gases ( 160 - 10nm). Rare gas (jet, cell, capillary). Forward Phase-matching. Laser 5-50fs, 1-30mJ, 10Hz-1kHz I L ~10 14 -10 15 Wcm -2 Linear pol. Spectral selection /focussing. Characterization Application.
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Coherent VUV generation :High order Harmonics in gases (160 - 10nm) Rare gas (jet, cell, capillary) Forward Phase-matching Laser 5-50fs, 1-30mJ, 10Hz-1kHz IL ~1014 -1015 Wcm-2 Linear pol. Spectral selection /focussing Characterization Application
Interaction of atoms with high laser field IL = 1013 -1017 W/cm2 field-electron momentum transfer Re-collision Multi-ionization 3- Recombination Above-threshold Ionization (ATI) Ultra-short (as) XUV burst wUVX = Ec + Ip Emission timete 2- Acceleration ELaser ELaser 1- Tunnel ionization ti te time xelec
Discrete / broadband XUV emission Ne Phase of XUV emission dfXUV = a dIL+ te dwXUV • Single harmonic (Salières et al. Science 2001) • Broadband emission (Paul et al. Science 2001, Mairesse Science 2003) Characterization of attosecond pulse train Harmonic phase fq≈qfLaser+ a IL Coherence properties
Attosecond time structure and dynamics EX(t) =SAqe-iwq(t -teq) N H25-33 (N = 5) <w25-33>, te H35-43 H45-53 <w35-43>, te H55-63 H25-63 t =150 as Energy wUVX Electronic trajectory in the laser field Proof of semi-classical three-step model Dinu et al., PRL 2003 Mairesse et al, PRL 2004
Energy / Peak power • Scaling laser energy and medium at constant IL(Laserlab I3 ) 10µJ
Spectral selection • Grating time stretch Al • Silica plates + metallic filters RIR ~ 10-4 In, Sn • Multilayer mirrors (l< 40 nm)
Spatial Coherence of High Harmonics Collab. Lab. Charles Fabry Orsay g = 0.5 : Coherent flux ~ 75% Total flux Fresnel bi-mirror Interferometer H13 (15) 61nm d=1mm d=2mm d=3mm Le Déroff et al. PRA 61 (2000) 043802
Focussing • Multilayer spherical M • Bragg Fresnel lens (Mo/Si) f=200 mm f=50mm • Parabola f=70mm 2.5 µm Zeitoun et al. LOA-LIXAM 1µJ at 20eV : IUVX ~ 1014 W.cm-2
Mutually coherent harmonic sources x= 80µm 180µm 380µm 600µm • Separated spatially x H17 Spatial interferometry • Separated temporally t Spectral interferometry l
Temporal properties Dl/l ~10-3 -10-2 Coherence time < pulse duration Frequency modulation :
Complete characterization of an XUV pulsePrinciple of SPIDER in the visible • 2 Replicas • Temporal delay t • Spectral shift W t w0+W w0 Grating w Spectral interference w0 Reconstruction ofE(w) and j(w)from the spectral interference pattern C. Iaconis & I.A. Walmsley, Optics Letters 23 (1998)
Transposition in XUV : “Dazzling SPIDER” wq+W wq t HHGTransfer as W=q.dwon harmonic q W is measured on the harmonic spectra w0 w0+dw w0 Gas Jet t Lens DAZZLER Laser Oscillator Amplifier F. Verluise et al., Optics Letters 25 (2000) HH Generator Acousto-optic filter Tailoring of the IR pulse Creation of two delayed replicas t is programmable and accurately set by the Dazzler Spectral shift of one of them dwset by cutting the wings of the laser spectrum Mairesse et al. PRL 2005
SPIDER XUV SPECTRUM SPIDER ALGORITHM Phase-locked XUV pulses Quadratic spectral phase Quadratic XUV temporal phase (IL-dependent) Negative linear chirp : wq = qwL + bqt
Temporal profile of harmonic emission FWHM=50fs FWHM=22fs Consistent Chirp Rate b11= 1.2 10 28 s-2 Varju et al., JMO 52, 379 (2005) Complete characterization of harmonic pulse
Amplification of harmonics in a laser medium Ph. Zeitoun et al., Nature 431, 426 (2004) 20 mJ, 30 fs HHG cell Toroidal Mirror Delay line l/4 1 J, 30 fs 10Hz Kr plasma Al Filter 3d94d J=0 32,6nm Collisions e - ions towards diagnostics 3d94p J=1 Ni-like Kr 8+: (Ne)3s23p63d10
Amplification in Krypton IX plasma at 32.8 nm Amplified harmonic HHG +XRL non synchronized XRL line
Prints of Laser at 32.8 nm Harmonic 25 alone Amplified Harmonic Amplification Factor : 15 à 200 (depending on seed level) Divergence : < 2 mrad • Amplification of harmonics in X-Ray laser : TUIXS (NEST)
Broad band Amplification > ASE regime L’amplification dépend du niveau d’injection Gss = 80 cm-1 Iseed ~ Isat/100 : strong amplification (x 200) Iseed ~ 4Isat : moderate amplification ( x 20)
Researchers - Collaborations - Contracts Attophysics group 2005 P. Breger H. Wabnitz PDoc B. Carré W. Boutu PhD M.-E. Couprie M. de Grazia PhD H. Merdji M. Labat PhD P. Monchicourt G. Lambert PhD P. Salière s Y. Mairesse PhD Collaborations Lab. Francis Perrin, CEA-Saclay Lab. Optique Appliquée, ENSTA-Ecole Polytechnique, Palaiseau Centre d’Etudes des Lasers Intenses et Applications, Bordeaux Lab. Interaction du rayonnement X Avec la Matière, Orsay Lab. Charles Fabry , Institut d’Optique, Orsay Service de Chimie Moléculaire, CEA-Saclay Lund Laser Center, Lund CUSBO, Politecnico Milano FOM Institute for Atomic and Molecular Physics, Amsterdam IESL- FORTH, Heraklion, Creete INOA-LENS, Firenze Brookhaven Nat Lab J. J. Thomson Lab., Univ. Reading Kurchatov Institute, Moscow • Contracts • 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
Saclay Laser-matter Interaction Center Power: 10TW Duration: 65 fs reprate: 10 Hz Intensity: >3.1018W/cm2 Plasma physics Particles acceleration Power: <1TW Duration: 45 fs Reprate: 20 Hz +1 line 560-650 nm (GW) 5 experimental stations Power: 0.4TW Duration: 30 fs Reprate: 1 kHz + 2 NOPAs (~5GW) Tunability: 520-750 nm UHI10 LUCA PLFA
B4.2Time-resolved diagnostics of dense plasmas 80 mm XUV interferometer using HH mutual coherence Collab. Lab. Ch. Fabry Orsay Magnif. ~10 Pump Imaging elliptical mirror B4C/Si multilayer (32nm) plasmaObject Resolution (object): 4 µm Field diam ~ 0.8 mm. Interferogram in virtual Object plane IR beam splitter Salières et al. PRL (1999) Descamps et al. Optics Lett. (2000)
Applications of Coherent XUV pulses • High intensity in the XUV (~ 1012W/cm2) : Non Linear processes • Short duration (10fs100as) /synchronization with laser : time-resolved studies • Intrinsic or mutual coherence : interferometry techniques Atomic 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). • 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)
Spectral selection • Grating time stretch • Silica plates + metallic filters
Spectral selection and focussing • Multilayer mirror (l< 40 nm) Parabola f=70mm Spherical Mirror f=200 mm 2.5 µm Zeitoun et al. LOA-LIXAM 1µJ at 20eV : IUVX ~ 1014 W.cm-2 • Bragg Fresnel lens (Mo/Si)
Complete characterization of XUV pulse : SPIDERPrinciple of IR SPIDER w • 2 Replicas • Temporal delay t • Spectral shift W Spectral interference t w1+W w1 Grating w0 Reconstruction ofj(w)from the spectral interference pattern C. Iaconis & I.A. Walmsley, Optics Letters 23 (1998)