RESONANCE INTERACTION OF ELECTROMAGNETIC BEAMS WITH SURFACE-WAVES AT THE INTERFACE BETWEEN LINEAR AND NONLINEAR MEDIA - EXCITATION AND SCATTERING

The effects arising during the interaction of bulk and surface waves a t the interface between linear and nonlinear media are studied. The re sonance excitation of weakly nonlinear surface p-polarized waves due t o diffraction of the crossing coherent light beams onto the self-consi stent diffraction grating produced by their interference field in the nonlinear medium is studied. The expressions for the amplitude of surf ace waves escaping from the beams' crossing region are found. The vari ous regimes of beam -nonlinear medium interaction are studied and the optimum conditions for exciting surface modes in the beams' crossing r egion and outside it are determined. The theory describing the scatter ing of incident bulk waves with surface ones is given. It is shown tha t with exceeding certain threshold values of the incident field streng th the energy transfer from incident beam into scattered beam and surf ace wave occurs, the energy transfer having an instability character. The backscattering is found to occur for the definite incidence angles . The characteristics of scattered field are calculated.