Two-color solitons under conditions of mismatches of the phase and group velocities

Abstract New soliton-like solutions of equations describing the pulsed modes of generation of the second harmonics accounting for mismatches of phase and group velocities are obtained. These solutions have the form of both bright and dark solitons. In both cases there are restrictions on the soliton temporal durations. These restrictions are determined by the mismatches of phase and group velocities and look different for the bright and dark solitons.