Bulk-to-surface-wave self-conversion in optically induced ionization processes - art. no. 066402

Nonlinear time evolution of a p-polarized wave mode with inhomogeneous tran sverse structure producing tunnel ionization of a gas is investigated by nu merical simulation and theoretical analysis. A phenomenon of trapping of el ectromagnetic radiation via its adiabatic conversion into surface waves gui ded by the field-created plasma structure is found out numerically. This pr ocess is accompanied by significant frequency downshifting of the electroma gnetic radiation. The underlying physical mechanism is explained using a si mple theoretical model. The described phenomena may play significant role i n the self-channeling and frequency tuning of intense (similar to 10(14)-10 (18) W/cm(2)) laser pulses in dense gases.