Analytical modeling of the resolution of photorefractive multiple quantum well spatial light modulators

An analytical model that includes lateral drift of photocarriers is develop ed to explain the experimental resolution of photorefractive multiple quant um well (MQW) devices. The model is in excellent agreement with a phenomeno logical fit proposed earlier and it follows a small intensity modulation mo del closely. Charge distributions with and without lateral drift of carrier s at the MQW interfaces are assumed in order to calculate the peak diffract ion efficiency as a function of grating period. An effective mobility-lifet ime product is used to account for the effect of lateral drift in the MQW r egion. It is shown that good agreement with experiment is obtained when lat eral drift is taken into account. Moreover, the model is applied to the stu dy of design tradeoff between resolution, sensitivity, and diffraction effi ciency which are all of crucial importance in the performance of practical devices. (C) 2000 American Institute of Physics. [S0021-8979(00)00622-8].