Effects of dark soliton on self-deflection of bright soliton in a separate bright-dark soliton pair

Abstract

Abstract Based on the theory of one-dimensional separate soliton pairs formed in a serial photorefractive crystal circuit, the effects of the dark soliton on the self-deflection of the bright one in one separate bright-dark soliton pair are investigated by taking the diffusion term into account. The numerical results obtained by solving the nonlinear propagation equation show that the bright soliton moves on a parabolic trajectory in the crystal and its spatial shift changes with the input intensity of the dark soliton. These effects are further studied using perturbation analysis and the characteristics of the spatial shift of the bright soliton varying with the input maximum intensity of the dark soltion are analysed. The position of the bright soliton at the output surface of the crystal can be determined accurately according to the formula obtained from perturbation method.