Abstract

A double phase conjugate mirror (DPCM) is a device that performs a phase conjugation simultaneously for two mutually incoherent pump beams via four-wave mixing in photorefractive media (Fig. 1).¹ Recent resurgence of interest to this scheme was caused by the theoretical controversy concerning the nonoscillating character of its operation.^2,3 The exact solution suggested by Zozulya is rather complicated, which makes difficult its application to a real experimental situation. We propose a simple approximate solution for the case of small angles between pump beams (α << 1/d, where l is the aperture of the interacting beams and d is the crystal thickness) which is typical of the nonstationary holographic recording in BSO-type crystals.⁴

© 1994 IEEE