Self-modulation effects in quadratically nonlinear materials

Abstract Under appropriate conditions, using the method of multiple scales, it is shown that an electromagnetic wave envelope propagating in a material with quadratic nonlinearity undergoes self-amplitude and phase modulation that is described by a nonlinear Schrodinger equation with cubic nonlinearity; therefore, for example, soliton propagation may be supported in this material through the same nonlinearity that generates χ (2) processes. Physical conditions and numerical examples are given for observing solitons.