Ga. Brost et al., MODULATION DEPENDENCE OF THE PHOTOREFRACTIVE RESPONSE WITH MOVING GRATINGS - NUMERICAL-ANALYSIS AND EXPERIMENT, Journal of the Optical Society of America. B, Optical physics, 11(9), 1994, pp. 1764-1772
The photorefractive response with moving gratings is investigated both
numerically and experimentally under varied fringe-velocity and modul
ation-depth (m = 0.002 to m = 1) conditions. The numerical analysis em
ploys a finite-difference technique to model photorefractive grating d
ynamics. The magnitude and the phase of the space-charge field are pre
sented in detail as functions of modulation depth, fringe velocity, an
d crystal parameters. Energy transfer and diffraction efficiency are f
ound to exhibit different response characteristics with modulation and
fringe velocity. Numerical results for two-wave mixing are generalize
d through analytical expressions that approximate the numerical soluti
ons. Illustrative experimental results are presented for Bi12SiO20.