Suppression of small-scale self-focusing in diverging beams

The solution of a nonlinear parabolic equation is used in a demonstration of the effectiveness of diverging (or converging) beams in suppression of small-scale self-focusing in high-power laser systems and also in control of such self-focusing. Characteristic radii of curvature of the wavefront of diverging beams are found as a function of the radiation power density and of the nonlinear coefficient of the medium in a laser. In the case of two-dimensional diverging beams the regular spatial distribution of the amplitude in the transverse direction is subject to distortions.