Second-order nonlinear interactions of space charge waves in photorefractive crystals

Second-order nonlinear effects in optics are well known. These are second harmonic generation and rectification of light waves. In this paper the results of experimental and theoretical investigations of the same effects, but in a system of other waves, namely, in the system of space charge waves (SCW) in photorefractive crystals are presented. The rectification causes reduction in the current flowing through the crystal, which can be as high as 25 %.