Localized states in the crystal characterized by the switching between self-focusing and defocusing Kerr type nonlinearities and the surface interaction

摘要

The theoretical description of the change in optical properties of nonlinear crystal along the surface caused by the propagation of localized excitations is proposed. The nonlinear response sharp changes between focusing and defocusing depending on field amplitude. We derive new types of surface states characterized by composite structure consisting of three parts. The influence of interaction of excitations with crystal surface on structure of the nonlinear surface states and peculiarities of the surface domain formation is analyzed. The new features of localization, which appear when the nonlinear response changes between self-focusing and defocusing, are described.