High-efficiency scattering in transient Brillouin-enhanced four-wave mixing

We report on an investigation of Brillouin-enhanced four-wave mixing which provides phase conjugate reflectivities greater than 10⁴. Theoretical modeling shows that the phase conjugate intensity grows with time until limited by pump depletion, and the main effect of varying the signal power is to increase the time delay before the conjugate beam reaches peak intensity. This is confirmed experimentally, and the maximum peak reflectivity is limited by the length of the laser pulses used in the experiment.