Observation Nonlinear Effects of a Laser Beam Interaction with Waveguide Photosensitive AgCl-Ag Films

Abstract

Nowadays a great attention is spared between various nonlinear optical effects to the spatio-temporal transformation of the laser beams such as: self-focusing, self- diffraction, bistability, optical turbulence and other transversal instabilities [1, 2]. The main part of experiments was accomplished in Kerr media placed in the resonator with a positive feedback. Comparatively a new object of the study of such effects is the thin lightsensitive films where the resonance interaction with the incident light is determined by Rayleigh scattering in the waveguide modes [3]. As a result the periodical structure on account of the interference between the incident beam and the scattering modes is formed in this film. This structure is developed within the beam action and in general manifest itself as the nonperfect diffraction grating. Its nonperfection is connected with that the periodical structure consists of the set of separate microgratings (domains). These microgratings are different from each other by the orientation of grating vectors K in regard to the principal direction K0 determined by the polarization vector E of the incident light beam. This work is devoted to the effects connected with the formation of the spontaneous periodical structures (SPS) of the waveguide nature in the films under the action of one single continuous Gaussian laser beam (P=5 mW, γ=633 nm) with arbitrary polarization.