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Compression of Laser Radiation in Plasmas Using Electromagnetic Cascading
Physical Review Letters (2005)
  • Serguei Y. Kalmykov
  • Gennady Shvets

Compressing high-power laser beams in plasmas via generation of a coherent cascade of electromagnetic sidebands is described. The technique requires two copropagating beams detuned by a near-resonant frequency, \Omega < \omega_{p}. The ponderomotive force of the laser beat wave drives an electron plasma wave which modifies the refractive index of plasma so as to produce a periodic phase modulation of the laser field with the beat period t_b = 2\pi/\Omega. A train of chirped laser beat notes (each of duration t_b) is thus created. The group velocity dispersion of radiation in plasma can then compress each beat note to a few-laser-cycle duration. As a result, a train of sharp electromagnetic spikes separated in time by t_b is formed. Depending on the plasma and laser parameters, chirping and compression can be implemented either concurrently in the same plasma or sequentially in different plasmas.

  • Electromagnetic cascading in plasma,
  • frequency combs,
  • negative group velocity dispersion,
  • trains of few-cycle relativistically intense pulses
Publication Date
Summer June 17, 2005
Citation Information
Serguei Y. Kalmykov and Gennady Shvets. "Compression of Laser Radiation in Plasmas Using Electromagnetic Cascading" Physical Review Letters Vol. 94 (2005)
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