Mid-infrared ZnGeP_2 parametric oscillator directly pumped by a pulsed 2 μm Tm-doped fiber laser

We have demonstrated what we believe to be the first mid-infrared optical parametric oscillator (OPO) pumped directly by a pulsed Tm-doped fiber laser. The Tm-fiber pump laser produces 30 ns pulses with a repetition rate of 30 kHz at a wavelength of 2 microm. The ZnGeP2 (ZGP) OPO produces 20 ns mid-IR pulses in the 3.4-3.9 microm and 4.1-4.7 microm spectral regions simultaneously. More than 658 mW of mid-IR output power has been generated with a total OPO slope efficiency greater than 35%.