Dynamic behavior of spatial solitons propagating along Scarf II parity–time symmetric cells

Abstract

Using a nonstationary state solution to the nonlinear Schrodinger equation (NLSE), we report the results of our numerical investigation on the swing behavior of spatial solitons propagating along waveguides whose refractive indices in the transverse direction are perturbed by Scarf II type parity–time symmetric profiles. We show that solitons, after entering parity–time symmetry (PTS) cells with Scarf II profiles will, in general, swing along the waveguide with nonuniform amplitude and period. Nevertheless, it is demonstrated that when the average incident position in the transverse direction is set at the center of the profile symmetry and the amplitude of the incident soliton exceeds a specific value, the soliton behavior could be approximated by a stationary-state solution to the NLSE and say it is almost self-trapped. Simulation also shows that, depending on the soliton’s initial average transverse input position, the swing behavior could be greatly influenced by the nonreciprocity of PTS cells.