Degenerate four-wave mixing of 10.6-μm radiation in Hg1−xCdxTe

We report observation of a large nonlinear optical susceptibility in HgCeTe for degenerate four-wave mixing of 10.6-μm radiation. Using pump pulses of 180 ns duration and 160 kW/cm2 peak intensity, nonlinear reflection coefficients of oiver 10% have been observed. The experimentally measured value of χ(3) is approximately 5.4×10−6 esu, in reasonable agreement with calculations based on a Drude model for the optically generated plasma. We have also observed nonlinear Fabry Perot effects in our samples.