6.5W mid-infrared ZnGeP2 parametric oscillator directly pumped by a Q-switched Tm3+-doped single-oscillator fiber laser

6.5 W of average power have been generated by a mid-infrared ZnGeP 2 (ZGP) optical parametric oscillator (OPO) pumped directly by a Q-switched Tm3+-doped single-oscillator fiber laser. The Tm 3+ -fiber pump laser based on a silica polarization-maintaining (PM) double-clad fiber provided average powers of up to 23 W at pulse widths of 65 ns at 40 kHz repetition rate. The ZnGeP 2 OPO produces 45 ns mid-IR pulses. The OPO slope efficiency was 40% and the optical-to-optical conversion efficiency 32%.