SPATIAL SOLITONS AND SHOCK-WAVES IN PHOTOREFRACTIVE CRYSTALS WITH NONLOCAL NONLINEARITY

An analytical model has been developed to describe both drift and diff usion mechanisms of nonlinear response (local and nonlocal components of nonlinearity) of photorefractive crystals (PRCs) on a microscopic l evel. Some types of stable self-consistent distributions of light inte nsity - bright and dark photorefractive spatial solitons - have been c onsidered. Paths of their propagation (self-bending) have been calcula ted and a possibility of formation of a new type of soliton-like distr ibutions - spatial shock waves - has been shown. Analysis of plane wav e modulation instability has been performed and specific spatial scale s of light distribution, resulting from self-action processes (fanning ), have been calculated. All the analytical results have been confirme d using computer simulation.