Generation of subcycle relativistic solitons by super intense laser pulsesin plasmas

2D and 3D particle in cell simulations of the interaction of ultra-short, h igh-intensity laser pulses with inhomogeneous plasmas show the formation of long-lived electromagnetic solitons. These solitons consist of electron de nsity depressions and intense electromagnetic field concentrations with a b igger amplitude and a lower frequency than those of the laser pulse. A sign ificant portion of the electromagnetic energy is trapped in the form of sol itons. Due to the plasma inhomogeneity, the solitons propagate toward the p lasma-vacuum interface where they radiate away their energy in the form of bursts of low frequency electromagnetic radiation. (C) 2001 Published by El sevier Science B.V.