We report on the observation of a multiple-pattern stability region in a photorefractive single-
feedback system. Whereas hexagonal patterns are predominant for feedback with positive …

We report on the appearance of running transverse waves and zigzag instabilities in
photorefractive counterpropagating two-wave mixing with a single external feedback mirror …

In this paper, we present an analytic solution for high gain two beam coupling in
photorefractive crystals where one of the input beams may be time dependent. This is an …

We report theoretical and experimental evidence for transverse modulational instability of
two counterpropagating beams in a photorefractive medium with no external feedback. A …

The effect of partial spatiotemporal coherence in photorefractive two-beam coupling is
studied theoretically and experimentally. Coupled-wave equations and a beam-propagation …

We show that manipulation and selection of optical patterns is possible by detuning the
frequency of one of the two waves in counterpropagating photorefractive two-wave mixing …

We report on a slowing down of light pulses using degenerate backward-wave four-wave
mixing in a photorefractive crystal. The delay and width of the output pulse for the amplified …

We propose and analyze a new type of phase conjugation between counterpropagating
beams in photorefractive materials based on diffraction from transmission gratings only. This …

(a/ax)E, = uE2, (alaxlE; = - VE: , Page 1 Volume 72. number 6 OPTICS COMMUNICATIONS I5
August 1989 BISTABILITY AT TWO-WAVE MIXING WITH FEEDBACK IN PHOTOREFRACTIVE …

Modulational instability in a photorefractive medium is studied in the presence of two-wave
mixing. We then propose and derive a model for forward four-wave mixing in the …