Spatiotemporal self-focusing and splitting of a femtosecond, multiterawatt, relativistic laser pulse in an underdense plasma

Abstract

The dynamics of ultrashort, high-power laser pulses in underdense plasmas differs dramatically from that of long laser beams. We present the results of numerical studies of this dynamics within a model, which systematically incorporates finite pulse length (i.e., dispersion) effects along with diffraction and nonlinear refraction in a strongly nonlinear relativistic regime. New spatio-temporal patterns of self-compression and self-focusing typical of ultrashort high-intensity laser pulses are analyzed. The parameters of our numerical simulations correspond to a new class of high-peak-power (⩾100 TW), ultrashort-pulsed laser systems, producing pulses with a duration in the 10–20 femtosecond range.