New method for calculation of the self-interaction and its application to an analysis of the shift of saturated absorption resonances in Gaussian beams

A new modification of the generalized method of moments is used to derive a system of differential equations which describe the behavior of a Gaussian beam in a nonlinear medium. This modification is used in an analysis of an asymmetry and frequency shifts of saturated absorption resonances and dispersion due to light-induced aperture and lens-like properties of the medium.