Coherently coupled screening spatial soliton pairs due to the two-photon photorefractive effect

Abstract

A theoretical study of coherently coupled spatial soliton pairs propagating along the same line in biased two-photon photorefractive crystals is presented. Our results show that coherently coupled bright–bright and dark–dark soliton pairs propagating collinearly can be supported in a steady-state regime under appropriate conditions. Moreover, the effects of the intensity ratio, the initial phase difference between two incident coherent beams, and various external bias fields on the existence conditions and properties of these soliton pairs have been discussed in detail. The stability of these soliton pairs has also been discussed by means of beam propagation methods. Finally, the temperature dependence of the dark irradiance and diffusion process on the intensity profiles and self-deflection of coherently coupled bright–bright soliton pairs are also analyzed.