Thomas Kuehl. GSI Helmholtz Center Darmstadt Helmholtz Institute Jena JoGu University Mainz. IZEST- Workshop Livermore July

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1 Experiments towards high-efficiency high-power plasma amplification using existing resources and installations 1 Thomas Kuehl GSI Helmholtz Center Darmstadt Helmholtz Institute Jena JoGu University Mainz IZEST- Workshop Livermore July

2 Outline Some basic remarks on SRS Some status on present experiments from Strathclyde,RAL and Jena/GSI PHELIX as another good candidate for high energy SRS development

3 3 Where to go... Revolutioniary new physics at higher intensities Particle physics Acceleration... [Mourou, Optics Com., 285, 2012]

4 FAIR A key laboratory for HED and ultrahigh field physics! SIS 100 /300 APPA Cave

5 Chirped-pulse amplification short pulse oscillator t dispersive delay line solid state amplifier(s) t Chirped-pulse amplification (CPA) becomes problematic due to damash isues in the compressor pulse compressor t t 5

6 Alternative solution:

7 SRS Constraints Pump beam: thermal plasma wave pump Raman Forward Scattering (RFS) Seed beam: seed RFS modulational instability filamentation, self focusing Plasma wave: wave breaking Landau damping 7

8 8 SRS Amplification Instabilities efficiently suppressed by low intensity and moderate plasma density. Pump chirp and density gradient can also help. Growth rate: Γ = k 4 c a 0 ω pe ω ek ω 0 ω ek 1 2 a 0 = λ μm I W/cm 2 ω pe ~ n e plasma frequency, e- density ω ek = ω 2 pe + 3 k 2 v 2 e v e electron velocity Need high intensity and high density to increase efficiency.

9 To Do List: Test the influence of small scale perturbations of the laser and plasma properties (plasma density, pulse energy, pointing) on the amplification process. Measure the ASE contrast and existence of pre-pulses to identify their roles in SRBS Identify the conditions for the onset of non-linear and competing processes, which limit the amplification Estimate the parameters for the onset of amplified post pulses due to Burnham Chiao ringing and suppress these by control the interaction length. Compare experimental scaling laws with those predicted by PIC simulations and Vlasov based codes. Compare amplification of wide pump pulses with energies of up to 10 s of Joules, to estimate the scaling.

10 Plasma as an Amplifying Medium: Raman CPA and the Transition to the Nonlinear Regime D.A. Jaroszynski 1, G. Vieux 1, X. Yang 1, A. Lyachev 2, B. Ersfeld 1, G. Raj 1, J.P. Farmer 1, M.S. Hur 3, R.C. Issac 1, E. Brunetti 1, S. Cipiccia 1, D.W. Grant 1, S.M. Wiggins 1, G.H. Welsh 1, N. Lemos 4, J.M. Dias 4, R. Heathcote 2 1 University of Strathclyde, Department of Physics, Glasgow G4 0NG, UK 2 Central Laser Facility, Didcot, OX11 0QX. UK, 3 UNIST, Banyeon-ri 100, Ulju-gun, Ulstan , South Korea, 4 GoLP/Insituto de Plasmas e Fusão Nuclear, Lisbon, Portugal Gain as a function of pump intensity Broadband amplificatio

11 Experiments at RAL (a) (b) wavelength [nm] wavelength [nm] (a) Measured spectrum of amplified spontaneous Raman emission. (b) Spectrum of ASE and the amplified probe for 50 J pump.

12 Stimulated Raman Backscattering at JETI B. Landgraf 1,2, B. Aurand 2,3,G. Lehmann 5,T. Gangolf 1, M. Schnell 1, T. Kühl 2,3,4, Ch. Spielmann 1,2 1 Institute of Optics and Quantum Electronics, Abbe Center of Photonics, Jena 2 Helmholtz Institute Jena, Jena 3 GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt 4 Johannes Gutenberg University, Mainz 5 Heinrich Heine University, Düsseldorf

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14 14 Seed Pulse Courtesy of J. Polz

15 r position 17 Gas Target Characterization Phaseshift over angle angle 3D Tomographic Reconstruction for neutral density profiles Performance: Density resolution: Δn > few cm -3 Temporal resolution: Δt > 0.1 ms Spatial resolution: Δx > 60 µm

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17 19 Spectra Amplification Bandwidth 90nm 1/e 2 80nm 1/e 2

18 20 Calculated Transform Limit Results from spectra measurement: 90nm 1/e 2 bandwidth, 17fs From 35nm, 30fs Pump!

19 High Intensity Laser [Mourou, Optics Com., 285, 2012] 21

20 Establishing the Parameter Range of Stimulated Raman Backscattering in Plasma as a Potential Novel High Power Amplifier B. Landgraf a,b, T. Gangolf b B. Aurand a,c, G. Lehmann e, S. Cipiccia f, G. Vieux f, S.M. Wiggins f, E.Brunetti f, G. Welsh f, V. Bagnoud c, T. Kühl a,c,d, Ch. Spielmann a,b, D.A. Jaroszynski f*, a Helmholtz Institute Jena, Helmholtzweg 4, Jena, Germany; b Institute of Optics and Quantum Electronics, Abbe Center of Photonics, Friedrich-Schiller University Jena, Max Wien Platz 1, Jena, Germany; c GSI Helmholtzzentrum fuer Schwerionenforschung, Planckstraße 1, Darmstadt, Germany; d Johannes Gutenberg University Mainz, Saarstr. 21, Mainz, Germany; e Heinrich Heine Universität, Universitätsstr. 1, Düsseldorf; f Scottish Centre for the Application of Plasma-based Accelerators, University of Strathclyde, Glasgow G4 0NG, Scotland, UK

21 PHELIX the petawatt high energy GSI sensor Main Amplifier Sensor diagnostics fs Front End Target chamber Z6 experimental area Laser Bay Pre-amplifier 2 x 19 mm heads 1 x 45 mm head Fiber ns Front End Injection box TW compressor X-ray Lab (low energy) Heavy ions Faraday Isolator Double-pass 31.5 cm amplifier Switch Yards Target Chamber Petawatt Compressor 70 m 2w 100-TW compressor

22 PHELIX the petawatt high energy GSI sensor Main Amplifier Sensor diagnostics fs Front End Target chamber Z6 experimental area Laser Bay Pre-amplifier 2 x 19 mm heads 1 x 45 mm head Fiber ns Front End Injection box TW compressor X-ray Lab (low energy) Heavy ions Faraday Isolator Double-pass 31.5 cm amplifier Switch Yards Target Chamber Petawatt Compressor 70 m 2w 100-TW compressor

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24 Present performance Long pulse 1w Long pulse 2w Short pulse Pulse duration ns ns ps On-target energy kj Up to 200 J 200 J Maximum intensity Wcm Wcm -2 Repetition rate at joule level Repetition rate at maximum power 1 shot every 3 min 1 shot every 1h Temporal contrast 50 db Better than 10 10

25 Bandwidth of the pump should be high to suppress spontaneous process No Filter Lyot Filter Experimental MA exit 5.5 nm 11.8 nm nm t = /c t = 340 fs Wavelength (nm) PHELIX uses passiv notch filter to reach 5 nm wavelength (nm)

26 The uopa as a contrast improving module short pulse oscillator uopa stretcher amplifier compressor target uopa pump Contrast: Signal to noise ratio Minimum noise due to quantum limit increase signal instead No ASE, Parametric noise confined to pump pulse duration 33rd International Workshop on Physics of High Energy Density in Matter Florian Wagner f.wagner@gsi.de C. Dorrer et al., Opt. Lett. 32, 2143 (2007)

27 The uopa as a contrast improving module short pulse oscillator uopa stretcher amplifier compressor target uopa pump Contrast: Signal to noise ratio Minimum noise due to quantum limit increase signal instead No ASE, Parametric noise confined to pump pulse duration 33rd International Workshop on Physics of High Energy Density in Matter Florian Wagner f.wagner@gsi.de C. Dorrer et al., Opt. Lett. 32, 2143 (2007)

28 cross-correlation signal Experimental results no uopa Gain 2.2 Gain 22 Gain 230 Gain Gain time [ps] 33rd International Workshop on Physics of High Energy Density in Matter Florian Wagner f.wagner@gsi.de

29 intensity 10 0 now time delay (ps)

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31 Conclusion and outlook SRS Amplification is a stable process but application at high energy requires: Well defined high quality high energy pump Powerful seed source Gas target preparation and diagnostics Precise diagnostics Theoretical support >>>>>>> Cooperation between laboratories!