The surface waves propagating along the contact between the layer with the constant gradient of refractive index and photorefractive crystal

Abstract

We consider the photorefractive crystal with diffusion nonlinearity mechanism contacting with the linearly graded-index medium. The new types of the surface waves propagating along the contact are found and their properties are described. The transition between two types of the surface waves can be controlled by the waveguide temperature. The light field penetrates into the photorefractive crystal much deeper than into the graded-index medium. The intensity maxima monotonically increase with an increase in the propagation constant, and monotonically decrease with an increase in the temperature. The localization length of the surface waves decreases with an increase in the characteristic distance the graded-index medium and with a decrease in the propagation constant and the temperature. The discrete spectrum of the propagation constant for the particular waveguide mode corresponding to the case of exponential damping of intensity maxima of the surface waves with an increasing temperature is obtained. It is shown that the intensity maxima in the photorefractive crystal depend parabolic on the temperature at low temperature waveguide mode.