Depolarization of radiation from high-power neodymium lasers and second harmonic generation of partly depolarized radiation

A theoretical analysis is made of two mechanisms (linear and nonlinear) of depolarization of radiation emitted by high-power solid-state glass lasers: these mechanisms are anisotropy-induced in the active elements and a nonlinear rotation of the polarization ellipse. In the cases of linear and circular polarization of practical interest, a qualitative and numerical analysis is made of the influence of depolarization of the radiation on second harmonic generation by the second type of interaction in KDP crystals. It is shown that in a field of partly depolarized radiation the second harmonic generation efficiency is limited mainly by depolarization of the radiation.