Self-bending of photorefractive solitons

Self-bending of photorefractive solitons is caused by diffusion in photoref ractive crystals and becomes an important effect when the beam size is in t he range of the charge carriers diffusion length. In this paper we present an experimental and numerical examination of the beam bending dependence on relevant parameters such as the applied electric field and the beam intens ity. We demonstrate that the bending dependence on the electric field in th e low saturation regime has the form of a square function at low values of the field and becomes linear for higher values. For stronger saturation the curve gets the form of a square root function. The bending dependence on t he beam intensity has a maximum at defined intensity. The experimental data are compared with numerical simulations, giving a good qualitative agreeme nt. (C) 1999 Published by Elsevier Science B.V. All rights reserved.