We derive an analytic expression describing the intensity and field frequency dependence of photorefractive gain in two-beam coupling under an alternating square-wave electric field. We determine the frequency and intensity ranges over which the gain is maximum and time independent. Experimental results for Bi12GeO20 crystals are presented.
© 1989 Optical Society of America
C. Besson, J. M. C. Jonathan, A. Villing, G. Pauliat, and G. Roosen, "Influence of alternating field frequency on enhanced photorefractive gain in two-beam coupling," Opt. Lett. 14, 1359-1361 (1989)