Self-Channeling of Relativistic Laser Pulses in Large-Scale Underdense Plasmas

摘要

Relativistic self-focusing and channeling of intense laser pulses have beenstudied in underdense plasma using 2D PIC simulations, for different laserpowers and plasma densities. Analytical solutions for the stationary evacuatedchannels have been recovered in PIC simulations. It is shown that otherwisestable channels can accelerate electrons due to surface waves on the walls ofthe channels. Relativistic filaments with finite electron density are unstableto transverse modulations which lead in the nonlinear stage to the break-up oflaser pulses into independent filaments. Different regimes of relativisticself-focusing and channeling, including electron heating, transverseinstability and break-up of the filaments have been discussed and characterizedusing plasma density and laser power.