Propagation of surface waves along a dielectric layer in a photorefractive crystal with a diffusion mechanism for the nonlinearity formation

It is shown that TM-polarised surface waves, which exhibit a different character of their attenuation, can propagate along a dielectric layer separating photorefractive crystals with a diffusion mechanism of the nonlinearity formation. The wave profiles can be symmetric and antisymmetric with respect to the centre of the three-layer structure. For all considered wave types, dispersion equations are derived. The dependences of the propagation constant on the characteristics of the layered structure are found for longwavelength surface waves in an explicit analytical form, and the conditions for their existence are revealed. The influence of the temperature and thickness of the dielectric layer on the propagation regimes of surface waves and their characteristics is analysed.