Efficient Parametric Mixing in CdSe

We have obtained the first phase-matched nonlinear interaction in CdSe and have observed a 35% conversion efficiency for mixing 10.6 μ with a pump at 1.833 μ to generate a signal at 2.2 μ. The mixing process phase matches at 77° to the optic axis and confirms the predicted phase-matching angle. The measured nonlinear coefficient value of 2.5 × 10−22 mks agrees with previous results. The mixing experiment shows than an angle-tuned or pump-tuned infrared parametric oscillator is possible using CdSe as the nonlinear element.