Photorefractive two-beam coupling with an oscillating input signal is investigated, theoretically and experimentally. It is shown that analytic solutions to the band transport model predict the output signal to be phase shifted with respect to the input signal. From the phase shift, a response time, which is period dependent, can be determined. Experiments with two different crystals of BaTiO3:Rh with different dopant densities confirm theoretical predictions. In addition, it is determined that one of the crystals has shallow traps, while the other does not, suggesting that the shallow traps are reduced rhodium.
© 1999 Optical Society of AmericaPDF Article