Generation of tunable mid-IR (5.5-9.3 μm) from a 2-μm pumped ZnGeP2 optical parametric oscillator

A tunable mid-infrared optical parametric oscillator (OPO) has been demonstrated using a single ZnGeP2 (ZGP) crystal. A KTP OPO was pumped by an Nd:YAG laser to generate 2.02 mum-signal wave at the output, which is used for pumping a singly resonant angle-tuned ZGP OPO to generate mid-IR tunable from 5.5 to 9.3 mum. Maximum pump to idler (2-8 mum) conversion efficiency obtained, was similar to8.25%, which corresponds to similar to32% quantum efficiency. (C) 2004 Elsevier B.V. All rights reserved.