Experimental observations and simulations on relativistic self‐guiding of an ultra‐intense laser pulse in underdense plasmas

The experimental images of the sidescattered light from a plasma, created by the multiterawatt laser pulse propagating in a hydrogen gas jet, exhibit clear dependence on both gas jet pressure and laser power. Two‐ and three‐dimensional simulations of wave propagation, in presence of the relativistic electron mass increase and the ponderomotive expel of electrons, have been performed to reproduce the Thomson radiation from the plasma electrons. They show electron cavitation induced by the beam focusing, self‐focusing, self‐guiding, smoothing of the beam nonuniformities and, at larger power, beam filamentation. A bremsstrahlung model with account of the ionization, heating, expansion, and recombination dynamics of the gas, provides the plasma emission background. Both Thomson emission and bremsstrahlung are required to recover the experimental emission patterns. Among the interpretations, a scenario of laser self‐guiding over five Rayleigh lengths can be found for 10 TW laser power and 5×1018 cm−3 electron ...

[1]  Michael D. Perry,et al.  Ignition and high gain with ultrapowerful lasers , 1994 .

[2]  G. Mourou,et al.  Generation of 20-TW pulses of picosecond duration using chirped-pulse amplification in a Nd:glass power chain. , 1991, Optics letters.

[3]  Ritchie Relativistic self-focusing and channel formation in laser-plasma interactions. , 1994, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics.

[4]  Electron acceleration by laser wake field , 1995 .

[5]  G. Bonnaud,et al.  Relativistic and ponderomotive self‐focusing of a laser beam in a radially inhomogeneous plasma. I. Paraxial approximation , 1993 .

[6]  M. Perry,et al.  Spectral shaping in chirped-pulse amplification. , 1990, Optics letters.

[7]  C. Manus,et al.  MULTIPHOTON IONIZATION OF ATOMIC AND MOLECULAR HYDROGEN AT 0.53 . , 1973 .

[8]  A. Ghatak,et al.  Self-focusing of Laser Beams in Dielectrics: Plasmas and Semiconductors , 1974 .

[9]  Laser light forces and self-focusing in fully ionized plasmas , 1973 .

[10]  Luk,et al.  Relativistic and charge-displacement self-channeling of intense ultrashort laser pulses in plasmas. , 1992, Physical review. A, Atomic, molecular, and optical physics.

[11]  R. More Laser interactions with atoms, solids, and plasmas , 1994 .

[12]  Diana Anderson,et al.  Variational approach to nonlinear self‐focusing of Gaussian laser beams , 1977 .

[13]  R. Wilson The spectroscopy on non-thermal plasmas , 1962 .

[14]  L. Bonnet Model Calculations of H-Like Recombination Schemes , 1994 .

[15]  G. Bonnaud,et al.  Relativistic and ponderomotive self‐focusing of a laser beam in a radially inhomogeneous plasma. II. Beyond the paraxial approximation , 1994 .

[16]  Bardsley,et al.  Residual energy in plasmas produced by intense subpicosecond lasers. , 1991, Physical review. A, Atomic, molecular, and optical physics.

[17]  P. Lallemand,et al.  Self-Focusing of Laser Beams and Stimulated Raman Gain in Liquids , 1965 .

[18]  Mora,et al.  Self-focusing and Raman scattering of laser pulses in tenuous plasmas. , 1992, Physical review letters.

[19]  W. Lotz,et al.  Electron-impact ionization cross-sections and ionization rate coefficients for atoms and ions from hydrogen to calcium , 1968 .

[20]  G. Bekefi,et al.  Radiation Processes in Plasmas , 1969 .

[21]  M. Seaton Radiative Recombination of Hydrogenic Ions , 1959 .

[22]  Dyson,et al.  Experiments and simulations of tunnel-ionized plasmas. , 1992, Physical review. A, Atomic, molecular, and optical physics.

[23]  J. Shearer,et al.  Pair Production by Relativistic Electrons from an Intense Laser Focus , 1973 .

[24]  E. O. Schulz-Dubois,et al.  Laser Handbook , 1972 .

[25]  Eric Esarey,et al.  Nonlinear analysis of relativistic harmonic generation by intense lasers in plasmas , 1993 .

[26]  M. Rosen,et al.  Hydrodynamics of exploding foil x‐ray lasers , 1986 .

[27]  I. Hutchinson Principles of Plasma Diagnostics , 1987 .

[28]  S. P. Gill,et al.  Physics of Shock Waves and High-Temperature Hydrodynamic Phenomena , 2002 .

[29]  Campbell,et al.  Multiphoton ionization of the noble gases by an intense 1014-W/cm2 dye laser. , 1988, Physical review. A, General physics.

[30]  Donald P. Umstadter,et al.  Femtosecond dynamics of short-scale-length laser plasmas , 1993, Photonics West - Lasers and Applications in Science and Engineering.

[31]  N. H. Burnett,et al.  Cold-plasma production for recombination extreme-ultraviolet lasers by optical-field-induced ionization , 1989 .

[32]  Michael D. Feit,et al.  Beam nonparaxiality, filament formation, and beam breakup in the self-focusing of optical beams , 1988 .

[33]  Eder,et al.  Optical-field-ionized plasma x-ray lasers. , 1992, Physical review. A, Atomic, molecular, and optical physics.

[34]  Alex B Borisov,et al.  Stable self-channeling of intense ultraviolet pulses in underdense plasma, producing channels exceeding 100 Rayleigh lengths , 1994 .

[35]  S. Wilks,et al.  TABLETOP X-RAY LASERS , 1994 .