DIFFRACTION PROPERTIES OF MULTIPLE-BEAM PHOTOREFRACTIVE GRATINGS

We have analytically solved the problem of N mutually incoherent pairs of beams in photorefractive media, each pair of which shares a common grating. The results are applied to study simultaneous read-write of dynamic photorefractive holograms with beams of comparable intensity. The diffraction efficiency is shown to be a nonlinear function of the read-beam intensity and is nonreciprocal with respect to readout from the two input ports. A complete energy transfer between the two write beams occurs in a finite thickness of the photorefractive crystal, in contrast to the infinite thickness required in the standard two-beam coupling case. © 1990 Optical Society of America.