Self-conjugation of pump waves with "boiling" speckle structure via backward stimulated diffusive scattering in an Fe:KNbO3 crystal

We have investigated backward stimulated diffusive scattering of light with a time-varying speckle structure by photorefractive crystals in which the nonlinearity mechanism is diffusion-driven. We show that the efficiency and conjugated fraction for this process depend on the ratio of the coherence time to the dielectric relaxation time of the medium.