Fizika | Lézerek » Jéröme Faure - Ultrahigh Intensity Lasers, Physics and Applications

Source: http://www.doksinet Ultrahigh intensity lasers: physics and applications Jérôme FAURE Laboratoire d’Optique Appliquée UMR 7639 http://loa.enstafr/ Source: http://www.doksinet What is laser intensity I (W/cm2) ? !" 2w0 Example: E=1 J, w0=20 !m, !0=30 fs (1 fs= 10-15 s) I0=5"1018 W/cm2 High intensity femtosecond lasers Nonlinear phenomena ultrafast phenomena Source: http://www.doksinet Salle Jaune Laser 2m Source: http://www.doksinet Free electrons relativistic laser-plasma interaction Free electrons Laser-plasma interaction Tunnel ionization Bound electrons Nonlinear optics Illustration: the ponderomotive force on 1 electron • !"#$%&()*()"+,#&)-#".)/&/+0+1(0)+"(0)2)+()/"+&*2#.)+"(0)3) a0=0.1 =2 The ponderomotive force in a plasma 4 5(.#&617#)8&$#)/9,:#,)#"#$%&(,;) F! F ~ -dIlaser 4 <()+)/"+,6+;)$&#+%#,)+)=+>#-#".) Champ E! Laser vg ~ c Plasma

wakefields Pulse Electron density accelerating Ez Extreme accelerating fields: 100 GV/m instead of 10 MV/m Er focusing Use laser-plasma interaction for making particle accelerators Relativistic nonlinear optics: self-focusing Nonlinear refraction index Relativistic nonlinearity #(r)" <a2> The plasma can « guide » light What can we do with relativistic laserplasma interactions ? Fundamental questions: understand laser-plasma interaction, energy transfert from the laser to the plasma, nonlinear effects ! towards a control of these phenomena Advanced light/particle sources: Produce particule and radiation sources with novel properties: femtosecond electron bunches and femtosecond X-rays, high energy, compact Electrons, ions, X-rays, high harmonics Applications of these new light sources: imaging of dense matter medical applications (radiotherapy) Femtosecond probing of condensed matter Why plasmas: because LHC is so big !!! Plasmas: very high electric fields !

Reduce the size of accelerators The plasma wakefield as an accelerating cavity Cavité RF: 1 m Ez = 10-100 MV/m Onde plasma: 100 !m Ez = 10-100 GV/m The physics is comparable to this The laser pulse The electrons the wave (accelerating structure) Experimental principle laser electrons Gas jet What it looks like in reality Injection beam 130 mJ, 30 fs $fwhm=28" 23 !m I ~ 4"1017 W/cm2 Pump beam 670 mJ, 30 fs, $fwhm=21"18 !m I ~ 4"1018 W/cm2 Stable and tunable monoenergetic beams 3 mm gas jet Statistics (30 shots): E = 206 +/- 11 MeV charge = 13+/- 4 pC %E = 14 +/- 3 MeV %E/E = 6% J. Faure et al, Nature 431, 541 (2004) J. Faure et al, Nature 444, 737 (2006) C. Rechatin et al, Phys Rev Lett 102, 164801 (2009) C. Rechatin et al, Phys Rev Lett 103, 194804 (2009) Femtosecond electron bunches 108 electrons in 1.5 fs rms bunch !! O. Lundh et al, Nat Phys 2011 X-rays produced by relativistic electrons .! β! Electron ! β! mm plasma wigglers

synchrotrons free electron lasers Equipe A. Rousse et K Ta Phuoc (LOA) Why plasmas: because LCLS is so big !!! Use plasma cavities as a compact undulator Betatron radiation: fs X-ray source Radiation produced in a laser wakefield accelerator Characteristics of the source: - 105 photons/shot/0.1% BW @ 1 keV! - divergence: 10’s mrad! - Duration: 10’s fs! - Spectrum: 1-10 keV! - Source size: 1- 2 microns! Perspectives:! - Increase radiation energy by controlling electron trajectories! - Use PW lasers! 20 mrad E > 3 keV A. Rousse, K Ta Phuoc et al, Phys Rev Lett 2004 Compton scattering fs X-ray source Radiation produced at the collision between a laser pulse and a relativistic electron Characteristics of the source: - 105 photons/shot/0.1% BW @ 1 keV! - divergence: 10’s mrad! - Duration: 10’s fs! - Spectrum: 10-1000 keV! - Source size: 1- 2 microns! Perspectives:! - Produce a tunable and monochromatic source! - Use PW lasers! Brevet publié 2012! A motivation for

these advanced sources: Ultrafast dynamics in out-of-equilibrium condensed matter Pump-probe experiments on solids: solide ? #t pompe VUV – XUV photons: Photoemission* Electronic structure bands, gaps sonde X-rays (keV) or electrons (100 keV): Diffraction: crystal structure Atomic motion Femtoarpes Lab, Luca Perfetti (X), Marino Marsi (Orsay) A motivation for these advanced sources: Ultrafast dynamics in out-of-equilibrium condensed matter • Creation of strongly out of equilibrium states of matter • Dynamics of relaxation mechanisms: transfert of electronic energy to the lattice, electron-phonon coupling • But also new information on static physics through temporal discrimination • Dynamics of photo-induced phase transitions • Controlling phase transition with light ? • Examples: solid-liquid transition; insulator metal transition; structural transitions Ex: 1T-TaS2 Eichberger et al., Nature 468, 799 (2010) Electron diffraction on 1T-TaS2, Eichberger et al.,

Nature 2010 State of the art – current limitations fs X-ray and electron sources !"#$%&#((&()(*+#,-&)$.(#& ?@;)ABA@C)D+/+(;)@EBAEC)F#&6+(G;)HI!A)JKLMNO) P)MLL)8,C)$:#&#(%)ML)>#Q)HR&+G,) "+&0#)S)#3/#(,*7#;)"6%#.)+$$#,,) /)+#$$.+&()(*+#,-&012#$3,-) T#=+*"U,)0&9/)JB+"%#$:OC)V""#&U,)0&9/) JW+6X9&0O) B6/+$%)Y)"+&0#).*Z&+$1()#[$#($G) P)LL)8,)#"#$%&()X9($:#,C)MLRML])#^X9($:C)MLL)>#Q) Use plasmas to produce 10 fs electron bunches for diffraction ? The perspectives and challenges of advanced light/particle sources - Demonstration experiments have been performed (it works) Femtosecond bunches, high energy, compact - Physics is highly nonlinear: complex and hard to control - Make these sources truly useful and explore new physics - Project FEMTOELEC (J. FAURE, LOA): - develop kHz, MeV electron bunches with < 10 fs for electron diffraction applications - Develop a

middle energy plasma accelerator (100 MeV – 1 GeV) and X-ray sources (V. Malka, LOA, K Ta Phuoc LOA) - Increase electron energy: 10’s of GeV in a small laboratory staging of plasma accelerators: APPOLON project (PW laser) (A. Specka, LLR, LULI team) Accelerating ions is also possible J. Fuchs (LULI, X) A. Flacco (LOA, ENSTA-X) T. Ceccoti (SPAM, CEA Saclay) 27 Attosecond pulse generation from plasma mirrors <(%#&+$1()=*%:)+),".)%+&0#%) )+%)< MLM`)ab$6RK) @"*.)%+&0#%)J0"+,,C)6#%+"O) !"#$%#&())*)& ?"%&+,:&%)"+,#&)/9",#) d*,%&.#)) #"#$%&*$)-#".) ?"%&+R:*0:)"0:%)(%#(,%G) &E"6,%)$6/"#%#)*(2+1()) &B&#+1()8)+),"*.)#(,*%G)/"+,6+) &)!"#$%&#%()%*+,-%(./0"-%% F. Quéré (SPAM, CEA) F#(#&+1()8)+()%&+*()) 8)+c,#$(.)) /9",#,C)(#)/#&)$G$"#) R. Lopez-Martens (LOA, X) High intensity laser plasma interaction

in France (not exhaustive) LOA, ENSTA-Polytechnique: electron acceleration (V. Malka, J Faure, C Thaury) ion acceleration (A. Flacco) X-ray generation (K. Taphuoc, A Rousse) attosecond high-harmonic generation (R. Lopez-Martens) X-ray lasers (S. Sebban) LULI, Polytechnique: ion acceleration (J. Fuchs) fast-ignition (S. Baton) SPAM at CEA-SACLAY High-harmonics (B. Carré’s team, F Quéré) Ion acceleration, electron acceleration (T. Cecotti, P Martin’s team) High intensity laser plasma interaction in France (not exhaustive) LLR, Polytechnique Electron acceleration (A. Specka) LPGP, Orsay Electron acceleration (B. Cros) CELIA, Bordeaux X-ray sources for probing warm dense matter (F. Dorchies) High harmonic generation (E. Constant’s team) Fast ignition for inertial fusion (J. Santos, D Batani, V Tikhonchuk)