Relativistic solitons in laser-plasma interaction

We discuss existence and stability of electromagnetic solitons in a relativistic interaction of a linearly polarized laser light with uniform underdense cold plasma. In a weakly relativistic NLS model with local and non-local cubic nonlinearities, an one-dimensional standing electromagnetic soliton trapped in a localized density well, is analytically shown to be stable. By fully relativistic fluid-Maxwell simulations existence of a family of large amplitude relativistic solitons is revealed. Simple analytical estimates give the relation between the maximum amplitude of the soliton vector potential and its eigen-frequency, in agreement with simulation data.2nd International Conference on Superstrong Fields in Plasmas, Aug 27-Sep 01, 2001, Varenna, Ital