Influence of regular phase modulation on formation of optical solitons

Numerical and analytic investigations are made of the propagation of a phase-modulated optical pulse in a nonlinear waveguide. The evolution of such propagation is described by a nonlinear Schrödinger equation. It is shown that phase modulation is not an obstacle to the formation of a soliton if its depth does not exceed a critical value, which can be estimated using integrals of motion. A description is given of two scenarios of soliton destruction under the influence of modulation of the initial pulse.