Solitons in periodic optical structures with nonlinearity management

In this paper, we investigate the solitary wave propagation through the nonlinear periodic structure that consists of alternating layers of both positive and negative Kerr nonlinear coefficients along the propagation direction, in which the pulse dynamics is governed by the nonlinear coupled mode (NLCM) equations. Using the multiple scale analysis, the NLCM equations are reduced into the perturbed nonlinear Schrodinger (PNLS) type equation, which incorporates both the higher order dispersive effects and self-steepening effect. From the PNLS equation, dark solitary solutions have been constructed by an extended Tanh-function expansion method. The effects of the physical parameters for nonlinear periodic structure on soliton propagation are discussed.