High energy density physics with lasers at Joint Institute for High Temperatures

Transcription

1 High energy density physics with lasers at Joint Institute for High Temperatures N. E. Andreev Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow, Russia Workshop "The Laser Ascent to Subatomic Physics and Applications" 26 th April 2013 French Embassy in Moscow, Russia

2 FEMTOSECOND LASER SYSTEMS at JIHT Terawatt femtosecond Chrome:Forsterite laser system 1240 nm; 80 fs; 90 mj; 10 Hz Subterawatt femtosecond Ti:Sapphire kilohertz laser system 800 nm, 30 fs,1 khz, 2,5 mj Terawatt femtosecond Ti:Sapphire laser system 800 nm; 40 fs; 10 Hz, to 10 TW Maximum intensity of focused laser spot 3um in diameter I L W/cm 2

3 C 1, 0 0, 5 0, 0-0, 5-1, A Spatial and temporal resoled interferometry using a frequency-modulated probe pulse. Single shot diagnostics of shock phenomena in a picosecond range. Probe wavelength, nm Time ps Interferometer 7 probe 300 ps probe 300 пс Probe λ 0 =790 nm τ=300 ps Al Pump λ 0 =790 nm τ=40 fs F 0 =1 2 J/cm 2 Glass Target:Al films on glass substrate CCD Spectrometer pump 40 fs Range of measurements ps Temporal resolution 2 ps Spatial resolution 2μm. Displacement accuracy 2 3 nm In aluminum uniaxial shock compression is elastic up to 13 GPa. Shear strength achieves 3.4 ГПа. Spall strength is 6 8 GPa at extremely high strain rate ~(1 5) 10 9 s -1 ОИВТ HEL, GPa Crowhurst et al, 2011 Al 10 Whitley et al, 2011 Agranat et al, Gupta et al, 2009 Garkushin Winey et al, 2009 et al, ,1 Arvidsson et al, 1975 Spall strength of aluminum as a function of the strain rate 0, Distance, mm Decay of the elastic shock wave in aluminum. S. I. Ashitkov, M. B. Agranat, G. I. Kanel, P. S. Komarov, and V. E. Fortov JETP Lett, V. 92, p 568 (2010)

4 Formation of nanocavities in the surface layer of aluminum irradiated by a femtosecond laser pulse Ablation crater on the surface of Al target irradiated by laser pulse of 80 fs duration at intensity W/cm 2 (microinterferometry) For the first time by transmission electron microscopy (TEM) the formation of nano bubbles inside the modified surface layer of aluminum at a depth of nm below the surface was observed modified layer z, nm 100 A l Y, m k m Formation of nano porous structure caused by the process of nucleation in a streched metastable melt in the unloading wave and its subsequent rapid cooling. S. I. Ashitkov, N. A. Inogamov, V. V. Zhakhovskii, Yu. N. Emirov, M. B. Agranat,I. I. Oleinik, S. I. Anisimov, and V. E. Fortov «Formation of nanocavities in the surface layer of an aluminum target irradiated by a femtosecond laser pulse» JETP Lett, V. 95, p.192 (2012)

5 Femtosecond diagnostics of nonideal plasma created by laser irradiation of a solid target Femtosecond time resolved interferometric microscope Femtosecond laser ω Temporal resolution s Spatial resolution 2 μm Phase accuracy π /200 Delay line Probe beam 2ω CCD interferometer time-resolved interferometric microscopy Pump beam Target Amplitude (r) and phase () of the complex Reflection coefficient reconstruction Ag target pulse duration τ 100 fs I ~ W/cm 2

6 Wide-range two-temperature hydrodynamic model electron-ion exchange laser energy absorption electron heat conductivity thermal radiation flux Models for closure Two-temperature equation of state (ρ, T e, T i ) Electron heat conductivity (ρ, T e, T i ) Electron-ion exchange (ρ, T e, T i ) Complex dielectric function (ω, ρ, T e, T i ) Radiation and absorption coefficients

7 Wide range models of transport properties Dielectric function Thermal conductivity ε met is the sum of the interbandand the intraband Drude-like terms 2E 1 E eff E min,, E, T, T, n pl met e i i me r0 N.E. Andreev M.E. Veysman, V.P. Efremov, V.E. Fortov. High Temp. 41, 594 (2003) M.E. Povarnitsyn, N.E. Andreev, E.M. Apfelbaum, T.E. Itina, K.V. Khishchenko, O F. Kostenko, P.R. Levashov, M.E. Veysman. Appl. Surf. Sci. 258, (2012)

8 Experimental reflectivity dynamics for S- and P-polarized probe pulses Experimental reflectivity dynamics for the S- (blue triangles) and the P-polarized (red squares) probe pulses. Corresponding simulation results are pre-sented by the blue and red solid lines, respectively. Dash-and-dot lines show the reflectivity changes for frozen motion regime. K. Widmann, et al., Phys. Plasmas 8 (2001) In the experiment the bulk aluminum target was heated by normal incident laser pulse with intensity W/cm 2, laser wavelength 400 nm and full width at half maximum (FWHM) 120 fs. Two probe pulses with FWHM 110 fs, 800 nm wavelength and angle of incidence 45 were used Mikhail E. Povarnitsyn, Nikolay E. Andreev, Eugeny M. Apfelbaum, Tatiana E. Itina, Konstatntin V. Khishchenko, Oleg F. Kostenko, Pavel R. Levashov, Mikhail E. Veysman. Appl. Surf. Sci. 258, (2012)

9 JIHT RAS K a radiation of solids by short intense laser pulses nm, 80fs, W, 10 Hz Focusing system 5 4 X-ray Hamos Spectro meter Vacuum camera X-ray ~10 18 W/cm 2 Mg, Cu target nm, 40 fs Measurement of the reflected pulse Off-axis paraboloid (focal length 254mm). 2 - Motorized target unit with target holder. 3 - System for interactive control of focus spot. 4 Von Hamos spectrometer 5 Mirror (R=100%) Focal spot X-ray spectrometer Target Microscope objective Off-axis paraboloid D 1/e =14µm M. B. Agranat, N. E. Andreev, S. I. Ashitkov, A. V. Ovchinnikov, D. S. Sitnikov, V. E. Fortov, A. P. Shevelko, Generation of Ka radiation by a forsterite terawatt laser, JETP Lett. 83, 72 (2006) CCD

10 CHARACTERISTIC X-RAY X RADIATION under the ACTION of LASER PULSES on NANO-STRUCTURIZED TARGETS Von Hamos spectrometer Ti:S laser: τ L = 40 fs; I = W/cm 2 Spot Ø = 14 μm K α 8 μm Increased Ka yield from Cu foil with clusters 2,5 CCD θ E L k 0 ~1 μm hot e K yield, 10 8 phot/sr 2,0 1,5 1,0 0,5 ρ = πd/λ Accelerating laser field at a spherical cluster E 0 cos,,, e, it 1 r E s 1 1 L n1 1 s 1 i 2n 1Pn cos 1 jn rs bnhn. n1 K α yield Cu nano-wire target (GSI, Germany) 10 8 wires/cm 2, Ø=500nm 1 μm Cu polished foil Cu foil with wires Increase of K α yield Measured K α yield, phot s/ster pulse (0.95±0.2) 10 8 (1.6±0.2) Calculated K α yield, phot s/ster pulse [1] O.F. Kostenko, N.E. Andreev (2011) Contrib. Plasma Physics. V. 51. P [2] A.V. Ovchinnikov, O.F. Kostenko, O.V. Chefonov, O.N. Rosmej, N.E. Andreev, M.B. Agranat, J.L. Duan, J. Liu, V.E. Fortov (2011) Laser Part. Beams. V. 29. P. 249.

11 MEASUREMENTS OF HARD X-RAY YIELD AS A FUNCTION OF the LASER INTENSITY AND CONTRAST Yield of hard X-Ray radiation as a function of nanosecond laser contrast at small observation angle with respect to target surface. Laser energy 5 50 mj Laser intensity on target surface ~10 18 W/cm 2 Quantum efficiency of X-ray detector Распределение Laser intensity лазерного distribution on излучения target surface на поверхности мишени Yield of hard X-Ray radiation as a function of laser intensity. 10 μm Yield of hard X-Ray radiation ~ I 1.9±0.3, where I laser intensity, W/cm 2.

12 JIHT GSI PHELIX project Investigation of the energetic electron spectra in dependence on the laser contrast at relativistic laser intensities for effective generation of 20 kev Ka-radiation PHELIX-Laser IP2 8 chan IP4 8 channels CH-foil Ag-foil Pin-hole Holes: 2* 10 Filters: Cu Pb Pin-hole IP1 8 chan IP3 8 chan Holes: 2* 10 Filters: Cu Pb ~ 2.5 m IP, 40mm 340mm plexi, 6x3mm 23mm Ag-foil 1.2 mm Al or C-foil Single-hit CCD Laser, best focus ( ~ 15x20 um) Shot 17, E=98J; Target :100um Ag+plex + 666nm Al-foil 1.2 mm apart 3,0 2,5 10 um silver foil N K, 10 8 phot (J sr) -1 2,0 1,5 1/2 L 2 2 Th mc 1a MeV N 2 1 dnk 2 E0 Kα d de0 exp EL d T 0 h T E h k 1, I 0, W cm -2 e dn E d em 0 Kostenko O.F., Andreev N.E., Chefonov O.V., Ovchinnikov A.V., Rosmej O.N., Schoenlein A., Wiechula J. // Physics of Extreme States of Matter 2013, JIHT RAS: Moscow, P. 26. M. E. Povarnitsyn, N. E. Andreev, P. R. Levashov, K. V. Khishchenko, and O. N. Rosmej. Phys. of Plasmas, 19, (2012)

13 Shock waves in laser plasma EOS for HED Monochromatic X-ray backlighting scheme is developed, that allows to measure object density or chemical staff in precise, with time resolution of ~ 1ps, according to the parameters of backlighting laser source c Detector f tang f sag Shock wave in CH sliver initiated by 300 J 1 ns laser Spherical crystal a Obect Source () Transmission b The scheme has been applied in experiments for EOS, laboratory astrophysics, ICF studies with intense laser pulses Shock density profile and shock front velocity of 20 km/s are measured Shocked CH // together with LULI, CELIA Bordeaux, GSI Darmstadt

14 Methods and equipment for laser plasma diagnostics X-ray spectroscopy methods are being developed to study the parameters of relativistic laser and ion beam plasmas ns pulse fs pulse X-ray spectra of Mg Trident LANL The yield and energy distribution of hot electrons were investigated W/cm W/cm 2 no hot electrons f hot = 10% Open Atomic Database SPECTR-W 3 for Plasma Spectroscopy ant other Applications X-ray spectrometers, X-ray optical components and X-ray detectors are being developed and manufactured for various applications in HEDP studies

15 Hollow atom X-ray X spectroscopy for PW laser plasma When laser field intensity reaches the value of W/cm 2 plasma turns to radiation dominant kinetics regime Intense X-ray radiation of relativistic solid-density plasma dominates atomic kinetics and creates hollow atom states e e + e e e No X-ray radiation, No hot electrons 5 kev electrons tail, No X-rays Hollow atom spectroscopy measurements and simulations allow to determine the conditions of plasma of multi-pw lasers Ultra intense kev X-rays Combined // Phys. Rev. Lett. 110, (2013) Vulcan PW facility together with York Uni, and LANL

16 Proton radiography for laboratory astrophysics Proton radiography method is applied to measure EM field distribution in laboratory astrophysics experiments with colliding plasma flows initiated by kj ns laser pulses // together with LULI Ecole Polytechnique and Osaka University The appearance of vortex inhomogeneities along the interaction interface is registered caused by the development of Kelvin-Helmholz instabilites Electric field strength of 10 MV/m is estimated both from proton radiography and modeling Collisionless interaction area imaged by proton radiography with ~ 4 MeV protons // Phys. Rev. Lett. 108, (2012)

17 Applications of laser-triggered ion beams new high-time resolution diagnostic techniques, since the short ion pulse duration; ion beam radiography / imaging and lithography; applications in energy research (ion Fast Ignitor in the inertial fusion energy context); medical treatment (proton therapy, transmutation of short lived radioisotopes for positron emission tomography (PET) in hospitals); short neutron source; astrophysical phenomena in the Lab

18 JIHT RAS Expected potential of laser plasma acceleration of electrons Electric field of plasma wave (with phase velocity ~ c, p =2c/ p ): E P [V/m] 10 2 ( n e [cm 3 ] ) 1/2 1 g p / 0 = n / n 0 plasma wave amplitude; at = , n e = cm -3 : E P = GV/m maximum of accelerating gradient in traditional accelerators (RF linac): E RF ~ MV/m Exponential growth of the Livingston curve began tapering off around 1980

19 Laser plasma accelerator based concept for a Laser Plasma Linear Collider Injector techniques Staging techniques Bunch properties 10 GeV module Collisions, synchrotron losses, efficiency C.B. Schroeder et al., AAC Proceedings 2008: Leemans & Esarey, Physics Today, March 2009 W. Leemans

20 Scheme of one cascade of the laser wake-field accelerator Focusing system Plasma Accelerated electrons Electron injector Wake wave Laser pulse The product of gradient and length achieved in this experiment is 0.4 GV at a pressure of J, 51 fs Short intense laser pulse Y (r =0, ) Diagnostic laser pulse Wakefield p = p (t - z/c) N.E. Andreev, K Cassou, F Wojda, G Genoud, M Burza, O Lundh, A Persson, B Cros, V E Fortov and C-G Wahlstrom, NJP, v. 12, (2010) JIHT RAS

21 JIHT of RAS Computer simulation by the code LAPLAC accelerated electron bunch the bunch has acquired an energy of 2.2 GeV with a narrow energy spectrum and low emittance 5.4 mm mrad The total trapped and accelerated number of particles in the bunch is about 25% of the injected electrons Einj 3MeV Lb0 2 z 47μm 18 2 r0 37μm I W/cm PL/ Pcr 0.35 L Q b =10 pc R b0 =45m FWHM 31 fs laser energy 2.25 J n (0) cm r 1mmmrad Nr, rms P/ mc r L b R b 0.9 m E/E 1% N.E. Andreev, V.E. Baranov, B. Cros, V.E. Fortov, S.V. Kuznetsov, G. Maynard, P. Mora, NIM A (2011)

22 With thanks for collaboration to V.E. Baranov - Joint Institute for High Temperatures RAS, Russia B. Cros - CNRS-Universitè Paris XI, France E. Esarey - Lawrence Berkeley National Laboratory, USA V.E. Fortov - Joint Institute for High Temperatures RAS, Russia K.V. Khishchenko - Joint Institute for High Temperatures RAS, Russia O.F. Kostenko - Joint Institute for High Temperatures RAS, Russia W. Leemans - Lawrence Berkeley National Laboratory, USA P.R. Levashov - Joint Institute for High Temperatures RAS, Russia G. Maynard - CNRS-Universitè Paris XI, France P. Mora - CPHT, CNRS- Ecole Polytechnique, France M.E. Povarnitsyn - Joint Institute for High Temperatures RAS, Russia M.E. Veisman - Joint Institute for High Temperatures RAS, Russia Thank You for your attention!