LASER PREPARATION OF CESIUM ATOMS FOR DEGENERATE 4-WAVE-MIXING

We show that the nonlinear optical response of an atomic vapor can be enhanced by the utilization of a second laser which selectively alters the atomic populations. We use a second, state-preparation laser to assist the degenerate four wave mixing and observe a signal at a non-cyclic transition in cesium vapor. In the absence of this state-preparation laser, the non-cycling transition is subject to optical pumping and consequently the four wave mixing signal is not observed.