Spatiotemporal Dynamics of High-Intensity Ultrashort Laser Pulses in Strongly Nonlinear Regime

The spatiotemporal dynamics of high-intensity femtosecond laser pulses is studied in strongly nonlinear regime. The physical model is capable to describe ultrashort pulse propagation down to single-cycle regime at presence of ionization of the medium. The ionization contribution to the group velocity dispersion is introduced in the model. The pulse propagation is described by the nonlinear envelope equation. The propagation and material equations are solved self-consistently at realistic physical conditions. We have shown that, at typical laboratory scale distances, the linear processes, more particularly - the dispersion, play a secondary role, while the pulse propagation dynamics is ruled mainly by competitive nonlinear processes in neutrals and plasma.