Vectorial two-beam coupling with arbitrary shifted photorefractive gratings: An analytical approach

Abstract

An analytical solution is presented to the vectorial coupled wave equations for the steady state amplitudes of two waves interacting in cubic photorefractive crystals. The solution accounts for pump depletion as well as an arbitrary phase shift between the interference pattern and photorefractive grating. It is shown that bidirectional vectorial amplification and polarization orthogonalization of the interacting beams take place in photorefractive crystal with diffusion, drift or mixed mechanism of space-charge formation.

Effect of photoconductivity and dielectric constant of the photorefractive materials on two-beam coupling gain and phase-shifts for a single unidirectional photorefractive ring resonator

“…We have also derived the expressions for the two-beam coupling gain (i.e., gain factor) and photorefractive phase-shifts for the signal beam under the appropriate boundary conditions of the ring resonators. In the earlier published literatures [5,9,11,20,25,29], the influences of the photoconductivity and dielectric constant of photorefractive materials on the amplification of the two-wave mixing gain factor and photorefractive phase-shifts of the signal beam inside a single unidirectional ring resonator have not been explored in detail. In this paper, the above effects are considered in details and discussed on its performances.…”

“…Two-wave interactions in photorefractive crystals have been extensively studied both theoretically and experimentally in the last four decades [1][2][3][4][5][6][7][8][9]. Initially, several theories, all giving good agreement with the experimental results measured at the time, were in competition with each other [10][11][12][13][14].…”