6.5 W ZnGeP(2) OPO directly pumped by a Q-switched Tm(3+)-doped single-oscillator fiber laser.

An efficient actively Q-switched Tm³⁺-doped single-oscillator fiber laser based on a silica polarization-maintaining (PM) double-clad fiber provided average powers of 23 W at pulse widths of 65 ns at 40 kHz pulse repetition frequency. It was used to directly pump a ZnGeP₂ optical parametric oscillator (OPO). Up to 6.5 W were generated in mid-IR wavelength range.