Bilinear forms and vector bright solitons for a coupled nonlinear Schrödinger system with variable coefficients in an inhomogeneous optical fiber

Abstract

In this paper, outcomes of the study on the bilinear forms and vector bright solitons for a coupled nonlinear Schrödinger system with variable coefficients are presented, which describes the simultaneous pulse propagation of the M-field components in an inhomogeneous optical fiber, where M is a positive integer. Under the integrable condition, we derive the bilinear forms, which are different from those in the existing literatures, and obtain the bright N-soliton solutions, where N is a positive integer. When M = 3, via the asymptotic analysis, we find that the amplitudes of the bright solitons are dependent on the amplification/absorption effect, , and the velocities of the bright solitons are related to the group velocity dispersion, , where z represents the spatial coordinate. Head-on, overtaking and inelastic interactions, and bound states between the two solitons are presented. We extend our analysis to M fields to obtain the vector bright N-soliton solutions.