Optical soliton inelastic interacitons in nonlinear Schrödinger equation with variable coefficients model

It is shown that in systems described by nonlinear Schrödinger equation with variable coefficients, interaction of two solitons can carry an inelastic character. Inelastic collision solitons can lead to changes in their group velocities, amplitudes and durations. We consider some particular cases related to the separation of the soliton pair and formation of a bound state of two solitons. In the applied aspect these phenomena can be used to control the soliton interaction in optical fiber communications.