Modulation instability and collision dynamics of solitons in birefringence optical fibers

In this paper, we investigate soliton modulation instability and collision dynamics in the birefringence optical fibers. Soliton transmission in the picosecond or femtosecond range in optical fibers is described by the coupled hybrid nonlinear Schrödinger equations. We focus on the modulation instability of the plane wave and the gain spectrum under different parameters. The three-soliton solutions are used to analyze soliton collisions, and the asymptotic analysis is provided to reveal the properties of soliton collisions. The elastic and inelastic collisions of three-soliton are presented, and there exists the possibility of shape restoration of one or two solitons during the three-soliton inelastic collisions. The relevant results provide not only a new perspective for the realization of optical logic gates, but also theoretical value for the experimental observation of soliton collisions.