Sickle Mutually Pumped Phase-Conjugate Mirror: Theoretic and Experimental Demonstration

A new mutually pumped phase conjugator with a photorefractive copper-doped potassium sodium strontium barium niobate crystal is demonstrated, in which the beams travel along a geometric path similar to the outline of a sickle. The maximum reflectivity is as high as 168%. Phase-conjugate images are obtained. The two-interaction region theory, based on the coupled plane wave amplitude, is used to account for the main characteristics of the new phase conjugator. The threshold coupling strength which depends on the reflection loss and the incident beam ratio, is also investigated and calculated.