Solitary wave evolution of optical planar vortices in self-defocusing photorefractive media

Solitary wave evolution of optical planar vortices in isotropic self-defocusing photorefractive media is investigated in detail. We demonstrate that the formation of a planar vortex soliton intensively depends on the diameter and maximum intensity of the input vortex beam. The exact solutions of planar vortex solitons are obtained due to the Petviashvili iteration method. It is found that, with the increasing soliton maximum intensity, the soliton core will be gradually diminished to a minimum value.