Mutually Pumped Phase-Conjugate Mirror : Two Arches Configuration

A mutually pumped phase conjugator with a novel photorefractive crystal of copper-doped potassium sodium strontium barium niobate is reported, in which both incoherent beams are incident upon the negative c face and they travel in geometric paths similar to the outline of two arches. The maximum reflectivity attains 21%. The tolerance of the output to both incident angles and positions is assessed. No apparent cross talk is observed. A cross-readout mechanism is also used to explain phase-conjugate reflectivity production. It is verified that the configuration can be realized easily for a crystal with two longer a sides.