Optimization of the field of view of a Brillouin-enhanced four-wave-mixing phase conjugator

A Brillouin-enhanced four-wave mixing phase conjugator featuring a field of view that varies by approximately an order of magnitude, i.e., from 2 to 20 mrad, is described. We control this variable field of view by utilizing a slightly noncollinear pumping geometry and by adjusting the pump-pump frequency difference to optimize the phase mismatch for the overall process. A model that describes the interplay between frequency and geometry to the Brillouin-enhanced four-wave-mixing phase mismatch is found to predict the expandable field of view.