Frequency locking in a photorefractive phase-conjugate ring oscillator was studied by injecting a seed beam into the resonator. For a seed beam coherent with the pump, frequency locking of the oscillator was observed at large seed powers. At lower seed levels, the beat signal displayed multiple harmonics in its frequency behavior. No evidence of locking was found for a seed incoherent with respect to the pump.
© 1992 Optical Society of America
M. J. Rosker, R. Saxena, and I. McMichael, "Frequency locking in phase-conjugate ring oscillators," Opt. Lett. 17, 508-510 (1992)