Enhancement of Phase Modulation Detection Sensitivity in Ring Photorefractive Configurations

An adaptive ring photorefractive configuration, which can increase remarkably the sensitivity of the homodyne detection of high frequency light phase modulation, is proposed and analysed. For typical BaTiO3 photorefractive crystals, the enhancement factor can reach 100. However, the practical results can be limited by the light losses in the ring cavity and, in particular, inside the photorefractive sample.