Femtosecond parametric generation in ZnGeP2

We report traveling-wave optical parametric generation in short (2-mm) ZnGeP2 samples with reduced anomalous absorption, using femtosecond pump pulses near 2 mu m. The signal and the idler waves generated could be tuned from 2.5 to 10 mu m, and they extend the tunability of the beta-barium berate optical parametric generator used as a pump source to the mid-infrared. At a single-pass internal conversion efficiency of 2.5% we estimate pulse durations of 75 fs (signal near 3 mu m) and 200 fs (idler near 6 mu m). (C) 1999 Optical Society of America.