Change in the Optical Properties Near the Interface of Self-Focusing Nonlinear Media Depending on the Intensity of a Localized Light Beam

A model is proposed in which localized light propagation is described by the nonlinear Schrodinger equation with abruptly varying parameters and a positive coefficient of quadratic nonlinearity, as well as with a point potential simulating the interaction of excitations with the interface between waveguide layers. An exact solution of the equation is found and its parameters are analyzed depending on the intensity of this interaction and the field amplitude at a defect. It is shown that the field amplitude at the defect decreases when the wave interacts with the interface between the waveguide layers. Changes in the properties of the region near the boundary are described, which are associated with features of the field structure in the localized light beam.