Femtosecond soliton propagating in slow group-velocity fiber

Abstract

The slow group-velocity pulse in fiber described by nonlinear Schrodinger equation were demonstrated and investigated extensively. We derive a more generalized nonlinear Schrodinger equation as the superposition of monochromatic waves and numerically study the propagations of 2.5-fs fundamental and 5-fs second-order solitons. It is found that, for a slow-group velocity fiber, the magnitude of time shift is related with the group velocity and the more generalized NLSE is more suitable than the conventional generalized NLSE. When the pulse is slow down to 50% of normal group velocity (c/n(0)), the effect of the higher nonlinear terms is significant.