Nonlinear Physics of Laser-Plasma Interaction

Abstract

The nonlinear force called ponderomotive force becomes an important role in laser-plasma interaction for the case where the laser energy density is comparable to the plasma pressure. Since the plasma density perturbation is induced by the laser intensity non-uniformity and vice versa, the laser propagation and plasma dynamics are coupled to induce the exponential growth of such perturbations. One is filamentation instability breaking up a single laser beam to many small filaments. One is stimulated Raman and Brillouin instabilities reflecting the incident laser as another electromagnetic waves. Detailed experiment of linear and nonlinear Raman instability is reviewed, and its physical mechanism is studied as a standard case of such parametric instabilities.