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Title: Observation of Laser-Pulse Shortening in Nonlinear Plasma Waves

Abstract

We have measured the temporal shortening of an ultraintense laser pulse interacting with an underdense plasma. When interacting with strongly nonlinear plasma waves, the laser pulse is shortened from 38{+-}2 fs to the 10-14 fs level, with a 20% energy efficiency. The laser ponderomotive force excites a wakefield, which, along with relativistic self-phase modulation, broadens the laser spectrum and subsequently compresses the pulse. This mechanism is confirmed by 3D particle in cell simulations.

Authors:
; ; ; ; ;  [1]; ;  [2];  [3]
  1. Laboratoire d'Optique Appliquee, Ecole Polytechnique, ENSTA, CNRS, UMR 7639, 91761 Palaiseau (France)
  2. Institut fuer Theoretische Physik, 1 Heinrich-Heine-Universitaet Duesseldorf, 40225 Duesseldorf (Germany)
  3. Nuclear Engineering Research Laboratory, University of Tokyo, 22-2 Shirane-shirakata, Tokai, Naka, Ibaraki, 319-1188 (Japan)
Publication Date:
OSTI Identifier:
20699567
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 95; Journal Issue: 20; Other Information: DOI: 10.1103/PhysRevLett.95.205003; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ENERGY EFFICIENCY; LASERS; LIGHT TRANSMISSION; MODULATION; NONLINEAR PROBLEMS; PLASMA SIMULATION; PLASMA WAVES; PONDEROMOTIVE FORCE; PULSES; RELATIVISTIC PLASMA; WAKEFIELD ACCELERATORS

Citation Formats

Faure, J., Glinec, Y., Santos, J.J., Ewald, F., Rousseau, J.-P., Malka, V., Kiselev, S., Pukhov, A., and Hosokai, T. Observation of Laser-Pulse Shortening in Nonlinear Plasma Waves. United States: N. p., 2005. Web. doi:10.1103/PhysRevLett.95.205003.
Faure, J., Glinec, Y., Santos, J.J., Ewald, F., Rousseau, J.-P., Malka, V., Kiselev, S., Pukhov, A., & Hosokai, T. Observation of Laser-Pulse Shortening in Nonlinear Plasma Waves. United States. doi:10.1103/PhysRevLett.95.205003.
Faure, J., Glinec, Y., Santos, J.J., Ewald, F., Rousseau, J.-P., Malka, V., Kiselev, S., Pukhov, A., and Hosokai, T. Fri . "Observation of Laser-Pulse Shortening in Nonlinear Plasma Waves". United States. doi:10.1103/PhysRevLett.95.205003.
@article{osti_20699567,
title = {Observation of Laser-Pulse Shortening in Nonlinear Plasma Waves},
author = {Faure, J. and Glinec, Y. and Santos, J.J. and Ewald, F. and Rousseau, J.-P. and Malka, V. and Kiselev, S. and Pukhov, A. and Hosokai, T.},
abstractNote = {We have measured the temporal shortening of an ultraintense laser pulse interacting with an underdense plasma. When interacting with strongly nonlinear plasma waves, the laser pulse is shortened from 38{+-}2 fs to the 10-14 fs level, with a 20% energy efficiency. The laser ponderomotive force excites a wakefield, which, along with relativistic self-phase modulation, broadens the laser spectrum and subsequently compresses the pulse. This mechanism is confirmed by 3D particle in cell simulations.},
doi = {10.1103/PhysRevLett.95.205003},
journal = {Physical Review Letters},
number = 20,
volume = 95,
place = {United States},
year = {Fri Nov 11 00:00:00 EST 2005},
month = {Fri Nov 11 00:00:00 EST 2005}
}
  • A method for generating large-amplitude plasma waves, which utilizes an optimized train of independently adjustable, intense laser pulses, is discussed and analyzed. Both the pulse widths and interpulse spacings are optimally determined such that resonance is maintained and the plasma wave amplitude is maximized. By mitigating the effects of both phase and resonant detuning, and by reducing laser-plasma instabilities, the use of appropriately tailored multiple laser pulses is a highly advantageous technique for accelerating electrons. Practical methods of producing the required pulse trains are suggested.
  • A method for generating large-amplitude nonlinear plasma waves, which utilizes an optimized train of independently adjustable, intense laser pulses, is analyzed in one dimension both theoretically and numerically (using both Maxwell-fluid and particle-in-cell codes). Optimal pulse widths and interpulse spacings are computed for pulses with either square or finite-rise-time sine shapes. A resonant region of the plasma wave phase space is found where the plasma wave is driven most efficiently by the laser pulses. The width of this region, and thus the optimal finite-rise-time laser pulse width, was found to decrease with increasing background plasma density and plasma wave amplitude,more » while the nonlinear plasma wavelength, and thus the optimal interpulse spacing, increases. Also investigated are damping of the wave by trapped background electrons, and the sensitivities of the resonance to variations in the laser and plasma parameters. Resonant excitation is found to be superior for electron acceleration to either beatwave or single-pulse excitation because comparable plasma wave amplitudes may be generated at lower plasma densities, reducing electron-phase detuning, or at lower laser intensities, reducing laser-plasma instabilities. Practical experimental methods for producing the required pulse trains are discussed. {copyright}{ital 1996 American Institute of Physics.}« less
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