Narrow nonlinear-optical resonances in CdSSe-doped glass

We describe frequency-domain spectroscopy studies of glasses doped with CdS(1-x)Se(x) using low-power cw tunable dye lasers. The results show a narrow resonance (4.4 kHz at room temperature) in the backward nearly degenerate four-wave mixing spectrum, which we believe is determined by the phonon-mediated inverse lifetime of a deep level trap involved in the nonlinear response.