Abstract

Degenerate four-wave mixing (DFWM) in saturable media has been known for some time as an efficient mechanism for generating phase-conjugate wavefronts.¹ In particular, we have previously published results of high- reflectivity (R>>1) DFWM in inverted Nd:YAG.^2,3 In this present work we report on the results of recent DFWM experiments with orthogonally-polarized pump beams in a Hash lamp-pumped Nd:YAG amplifier. Using orthogonally-polarized pump-beams a phase-conjugate beam is produced which is orthogonally polarized to the input probe beam. We use this interaction geometry (see Fig. 1) to investigate directly the relative efficiencies of transmission and reflection gain- gratings written in the inverted Nd:YAG for both the production of phase-conjugate four- wave mixing and as a diffractive laser clement.

© 1993 Optical Society of America