Coupled wave analysis of anisotropic self-diffraction in photorefractive materials with an external electric field

Anisotropic self-diffraction in doped KNSBN crystals has been observed for the experimental configuration where the c-axis is parallel to the incident plane when an external electric field is applied. The space distribution of grating vector may be the main reason for the generation of anisotropic self-diffraction in our experimental configuration. The coupled wave equations and the numerical solutions including the space distribution of grating vector and the first two order space-charge field are presented. Both theoretical analysis and experimental results show that anisotropic self-diffracted light arises from the contribution of both incident beams. (C) 2000 Elsevier Science B.V. All rights reserved.