Introduction Compact 0.56 PW laser system Scalability to multi-petawatt power Conclusion

Petawatt OPCPA Lasers: Status and Perspectives V.V.Lozhkarev, G.I.Freidman, V.N.Ginzburg, E.V.Katin, E.A.Khazanov, A.V.Kirsanov, G.A.Luchinin, A.N.Mal'shakov, M.A.Martyanov, O.V.Palashov, A.K.Poteomkin, A.M.Sergeev, A.A.Shaykin and I.V.Yakovlev Institute of Applied Physics Russian Academy of Science Introduction Compact 0.56 PW laser system Scalability to multi-petawatt power Conclusion

Introduction. OPCPA vs CPA Advantages of OPCPA: + broad gain bandwidth + high aperture + considerable decrease in thermal loading + significantly lower level of ASE + very high gain + no self-lasing + no backscattering from a target Disadvantages of OPCPA: high precision synchronization high quality of a pump beam short (1ns) pump pulse duration

Introduction. Petawatt laser systems type I type II type III Gain medium Ti:sapphire KD*P Energy source Pump no 2ω Nd 2ω Nd Pump duration, ns no <30 1 Amplifier aperture, cm 40х40 10 40х40 Minimum duration, fs 150 20 20 Efficiency (1ω Nd фс), % 80 15 10 Number of PWs from 1 kj 1ω Nd 4(5) 8 ( 1.5 ) 4 Maximum power obtained, PW 1.3 PW LLNL, 1997 0.85 PW JAEA 2004 0.56 PW IAP 2006 Diffraction grating damage threshold Ti:sapphire damage threshold

Physics of OPCPA. KD*P vs KDP. superbroadband 1800 phasematching FWHM of gain spectra, cm -1 (lines) 1500 1200 900 600 300 0 generated phase matching λ signal =2λ pump =1053nm KD*P bandwidth KD P bandwidth KD*P absorption KDP absorption 750 850 950 1050 1150 1250 1350 signal wavelength, nm KD*P DKDP V.V.Lozhkarev, G.I.Freidman, V.N.Ginzburg, E.A.Khazanov, О.V.Palashov, A.M.Sergeev, I.V.Yakovlev. Laser Physics, 15, 1319 (2005). 0,35 0,3 0,25 1 1 10,2 = + 527nm 911nm 1250nm 0,15 0,1 0,05 0 ordinary wave absorbtion, cm -1 (dots)

Petawatt OPCPA Lasers: Status and Perspectives Introduction to PW lasers Compact 0.56 PW laser system Scalability to multi-petawatt power Conclusion

Compact 0.56 PW laser system. Architecture Synchronization system Nd:YLF Q-switch laser λ=1053nm 10mJ 12nc Pulse shaper Cr:Forsterite fs-laser λ=1250nm 2nJ 40 fs 1nJ 0.5 ns Stretcher 40 fs 0.5 ns 1mJ 1.5ns 1 J 1.5ns Two-stage Nd:YLF amplifier 2J 1.5 ns OPA I KD*P CW Yb:fiber pump 10W λ=1050 1080nm 2ω λ=911nm 0.8mJ 0.5ns OPA II KD*P λ=1250nm First phase (TW level) λ=911 nm 50 mj 0.5 ns Compressor 0.5 ns 50 fs 50 mj 50 fs 2Hz amplifier 300J 1ns 2ω 170J 1ns OPA III KD*P 10cm dia 38J 0.5ns Compressor 0.5ns 50fs 24J 43fs Second phase (PW level) Freidman G., Andreev N., Ginzburg V., Katin E., Khazanov E., Lozhkarev V., Palashov O.,

Compact 0.56 PW laser system. Key elements of tabletop 300 J laser spatial filter input beam shaping 85mm dia. polarizer 60mm dia. λ/4 λ/2 Faraday 10mm dia. KDP soft aperture Nd:YLF 1054 nm 2ω 1 J to pump OPA I, II spatial filters self-focusing suppression laser heads self-excitation suppression 30mm dia. second harmonic generation λ/4 λ/4 100mm dia. spatial filter 100mm dia. 2ω Martyanov M. A., Khazanov E.A., Poteomkin A. K., 180 J to pump OPA III

Compact 0.56 PW laser system. laser output beam 300J, 1ns 10 2.44λ/D=21μrad 50 μrad 1 0.9 0.8 20 0.7 30 0.6 40 0.5 50 0.4 0.3 60 0.2 70 0.1 0 10 20 30 40 50 60 70 0 90мм

Compact 0.56 PW laser system. Energy characteristics of final OPCPA Efficiency, % 40 35 30 25 20 15 10 Efficiency, % Pulse energy. J 38 J 40 35 30 25 20 15 10 Output pulse energy, J 2.44λ/D=21μrad 25μrad 1 0.9 5 5 0.8 0.7 0 0 30 60 90 120 150 180 Pump pulse energy, J 0 0.6 0.5 0.4 0.3 0.2 0.1

Compact 0.56 PW laser system. Compressed pulse 1 0.75 ACF experiment ACF of 33fs FTL pulse ACF, a.u. 0.5 0.25 0-200 -150-100 -50 0 50 100 150 200 time, fs 24 J /43 fs=0.56 PW Contrast: 10 8 (0.5ns window) 10 4 (1ps window) Lozhkarev V.V., Freidman G.I., Ginzburg V.N., Katin E.V., Khazanov E.A., Kirsanov A.V., Luchinin G.A., Mal'shakov A.N., Martyanov M.A., Palashov O.V., Poteomkin A.K., Sergeev A.M., Shaykin A.A., Yakovlev I.V.

Compact 0.56 PW laser system. Compressed pulse 10000 1000 CPA Vilnius U., Lithuania Rutherford Lab, UK SIOM, China laser power, TW 100 10 1 0.1 0.56 PW Rochester, USA LLNL, USA IAP, Russia LLNL, USA Rutherford Lab, UK 0.01 0.001 1991 1996 2001 2006 year ILE, Japan JAEA, Japan SIOM, China Texas U., USA

Petawatt OPCPA Lasers: Status and Perspectives Introduction to PW lasers Compact 0.56 PW laser system Scalability to multi-petawatt power Conclusion

Scalability to multi-petawatt power. Routes to increase power and contrast POWER: + Pulse duration: x3 (15fs instead of 45fs) + OPCPA efficiency: x2 (40% instead of 20%) + Pump power x1.3: (230J instead of 180J) + Compressor efficiency x1.2 (79% instead of 66%) TOTAL: x11 ( 6PW instead of 0.56PW ) CONTRAST: Second harmonic generation in KDP crystal theory (includes self-focusing) predicts high efficiency crystal 100mm diameter and 0.5mm thickness was grown experiments are coming soon

Scalability to multi-petawatt power. Four started projects. VNIIEF (Sarov) + IAP, Russia, 2005-2008, 3PW OPCPA Rutherford Lab, UK, 2007-2011, 10PW OPCPA НiPER, pan-european, 2008-2018, 150PW / 2000PW OPCPA ELI, pan-european, 2008-2020 200PW OPCPA or Ti:sapphire

Scalability to multi-petawatt power. Sarov N.Novgorod. Synchronization system Nd:YLF Q-switch laser λ=1053nm 10mJ 12nc Pulse shaper Cr:Forsterite fs-laser λ=1250nm 2nJ 40 fs 1nJ 0.5 ns Stretcher 40 fs 0.5 ns 1mJ 1.5ns 1 J 1.5ns Two-stage Nd:YLF amplifier 2J 1.5 ns OPA I KD*P CW Yb:fiber pump 10W λ=1050 1080nm 2ω λ=911nm 0.8mJ 0.5ns OPA II KD*P λ=1250nm First phase ( TW level) λ=911 nm 70 mj 0.5 ns Compressor 0.5 ns 70 fs 32 mj 70 fs 2Hz Nd:YLF Q-switch laser λ=1053nm amplifier 300J 1ns 2ω 180J 1ns OPA III KD*P 10cm dia 38J 0.5ns Second phase (PW level) Compressor 0.5ns 50fs 24J 43fs 10mJ 12nc Pulse shaper Nd:YLF amplifier amplifier 2kJ 1.5ns 2ω 1kJ 1.5ns OPA IV KD*P 20cm dia 150J 0.5ns Third phase ( 2 PW) Compressor 0.5ns 50fs 100J 50fs

Scalability to multi petawatt power. Sarov N.Novgorod. 100??fs November, 2008 OPCPA gain =35 Peak efficiency = 38% chirped pulse energy, J 75 50 25 0 55fs 600TW October,2008 0 200 400 600 800 1000 1200 Pump energy, J 2.44 λ/d = 12.2 μrad I.A. Belov, O.A. et al. Petawatt laser system of the "Luch" facility

Conclusion #1. OPCPA at 910 nm in DKDP is the best. No question. #2. There is only one question. Q.: The best or one of the best? A1: See message #1. 25μrad A2: Will live and see.

After conclusion Let s think about laser ceramics! Cr:YAG ceramics Nd,Yb:Re 2 O 3 ceramics (Re=Y,Lu,Sc) very wide aperture to amplify chirped pulses to the multikilojoule level, high conversion efficiency of narrow band laser pulses into chirped pulses, large gain bandwidth to amplify chirped pulses with less than 20 fs durations 1. Very wide aperture to amplify chirped pulses to the multikilojoule level 2. Large gain bandwidth to amplify chirped pulses with less than 50 fs durations 3. High conversion efficiency due to direct lamp pumping (lamps pump Nd and excitation transfers to Yb) Е.А.Khazanov, А.M.Sergeev. Laser Physics, 2007. Е.А.Khazanov, А.M.Sergeev. UFN, 2008.

Compact 0.56 PW laser system. Electon acceleration (preliminary results) Electrons energy spectrum, Numerical simulation drive pulse 1, vacuum tract 2, flat mirror 3, off-axis parabola 4, gas jet 5, foil partition 6, LANEX screen 7, CCD camera with vacuum window 8, probe pulse 9, delay line10, mirror 11, microscopic objective12, wedge

Compact 0.56 PW laser system. 120mm clear aperture ОPA OPA 120 mm clear aperture SHG From front-end system (911nm) 300 J 1054 nm pump pulse OPA 3 38J to compressor (911nm) To diagnostic 300 J 1054 nm 180 J 527 nm

Scalability to 100(s) petawatt power 18 fs pulse: Ripin D.J., Chudoba C., Gopinath J.T., Fujimoto J.G., Ippen E.P., Morgner U., Kartner F.X., Scheuer V., Angelow G., Tschudi T. // Optics Letters, 27, 61-63, 2002. Crazy ideas are welcome! Cr 4+ :YAG ceramics (CPA) 1 Cr:YAG Cr:YSGG Cr:YAG+Cr:YSGG spectra, a.u. 0.5 0 1000 1200 1400 1600 1800 2000 wave length, nm

Scalability to multi-petawatt power. Crazy ideas are welcome! Gain medium Energy source type I type II Ti:saphire type III DKDP type IV Cr:YAG ceramics Pump no 2ω Nd 2ω Nd 1ω Nd Pump duration, ns no <30 1 <30 Amplifier aperture, cm 40х40 8 40х40 >50 Minimum duration, fs 150 20 20 20 Efficiency (1ω Nd фс), % 80 15 10 25 Number of PWs from 1 kj 1ω Nd 4.5 (5) 8 ( 1.5 ) 4 10 Maximum power obtained, PW 1.3 LLNL, 1997 0.85 JAEA 2004 0.56 IAP 2006 10-10

Physics of OPCPA. Wideband phase-matching ω ω ω = + 1 2 ω ω 3 1 2 = ω = ω 10 20 + Ω Ω ( t) () t k r 10 v r v r 1 ϕ 12 2 Z k r Δk 2x ( ω 2 ) = k 3x r ( Ω ) = Δk( Ω ) z 0 ϕ 12 ( ) Ω r ϕ 13 k r k 2 20 3 k r Δk ( Ω) Δk(0) 0= phase-matching k 3 = k 0) + k 1 ( 2 (0) 2 Рис 1 2 dk1 dk 1 2z d k1 d k2z 2 + Ω 0( Ω 2 2 2 + dω dω Ω dω dω V =0 wideband phase-matching = V cos ϕ =0 super-wideband phase-matching 3 )