PHASE-MATCHED GRATINGS FOR ENHANCED FORWARD DEGENERATE 4-WAVE-MIXING

A phase-matched grating to enhance the second-order diffracted signals generated by forward degenerate four-wave mixing has been proposed and demonstrated for the first time to the authors' knowledge. Experiments have been performed with a cw Ar:Kr laser at 488 nm with a linear-nonlinear sandwich of glass slides and Alizarin yellow-doped epoxy resin films. Finite difference simulations have been used to model the process successfully, with finite beam size effects and deviations from an ideal response of the material taken into account. The possibilities for optical processing applications are assessed in the light of these results.