MID-IR ABSORPTION IN AGGASE2 OPTICAL PARAMETRIC OSCILLATOR CRYSTALS

We report new experimental results on the spectral, thermal, and orien tational characteristics of stoichiometry-dependent mid-IR absorption in AgGaSe2 crystals. In currently available material, this absorption poses an obstacle to the power scaling of the 2-mum-pumped AgGaSe2 opt ical parametric oscillator (OPO). Preliminary experiments have indicat ed that this absorption could be substantially reduced by optimization of the process parameters during crystal growth and annealing. OPO ou tput powers approaching 10 W may be achievable by using optimized mate rial.