Linear and Nonlinear Optical Properties of ZnGeP2 Crystal for Infrared Laser Device Applications: Revisited

Measurement of refractive indices in the spectral bands 9-11 (mu)m and 1.32 (mu)m from a cw CO2 laser and a Q-switched Nd:YAG laser, respectively, is reported in a ZnGeP2 crystal. A new set of Sellmeier dispersion relations has been derived from the measured refractive indices data in this crystal. Second-harmonic generation (SHG) of CO2 laser radiation in this crystal is also reported. It is also seen that the previously reported phase-matching data for others experiments in SHG and optical parametric devices is explained satisfactorily with this new set of Sellmeier dispersion relation.