Abstract

Rectangular prisms of photorefractive crystals such as barium titanate and strontium barium niobate have been used in the past as high-reflectivity high-fidelity self-pumped phase conjugators. The effect is more easily seen in barium titanate than strontium niobate. Although the mechanism of the phase conjugation has been the subject of considerable debate, it has been generally accepted that total internal reflection usually plays an important role. We have fabricated a ring self-pumped phase conjugator using total internal reflection in a triangular prism of strontium barium niobate. The crystal is cut so that reflection gratings cannot play an appreciable role. The phase-conjugate reflectivity and fidelity of the rectangular and triangular devices are compared.

© 1988 Optical Society of America