Polarization-preserving wavefront reversal by four-wave mixing in photoanisotropic materials.

A method of polarization (vector) wavefront reversal by four-wave mixing in a photoanisotropic material is described. Jones matrices, describing the dynamic holographic gratings recorded in the material at arbitrary polarization of the signal wave, are derived. They are employed to define the conditions for generating a wave that is fully conjugate (by polarization as well) to the signal wave. The way to achieving these conditions by optically controlling the anisotropy of the nonlinear medium is demonstrated experimentally.