We present the theory for photorefractive two-beam coupling without optical activity in cubic crystals rotated around the  axis. We also describe two-beam coupling experiments in InP:Fe that fit the theory closely. The 15.5% gain enhancement for grating wave vectors aligned along the 〈111〉 directions is demonstrated explicitly.
© 1990 Optical Society of America
Original Manuscript: July 31, 1989
Manuscript Accepted: December 11, 1989
Published: February 15, 1990
J. Strait, N. V. Kukhtarev, and J. D. Reed, "Orientational dependence of photorefractive two-beam coupling in InP:Fe," Opt. Lett. 15, 209-211 (1990)