Abstract

The scheme of phase conjugation (PC) in four-wave mixing with feedback (FWMF) using an amplifier in the feedback loop is a laser controlled by an external optical signal. Note that in this scheme the generation is, generally, developed simultaneously in two directions and is withdrawn through a nonlinear medium as the useful reflected wave E_r counter to the signal and the parasitic wave E_p copropagating with the signal. The energy of the parasitic wave E_p often proves to be higher than the energy of the reflected wave E_r.^1,2 Thus, the problem of providing the unidirectional propagation of the conjugate wave is urgent.

© 1994 IEEE