Long-Wave Infrared ZnGeP2 Optical Parametric Oscillator With a Wide Tuning Range by Rotating a Diffraction Grating

We report a ZnGeP2 optical parametric oscillator (OPO) with a wide tuning range in the long-wave infrared. The OPO was pumped by a Ho: YLF laser with high peak power, and a resonate cavity with a diffraction grating was used. A tunable long-wave laser with the wavelength of 8.45-11.37 mu m was achieved by rotating the grating. Meanwhile, the linewidth was less than 61 nm at the wavelength within the tunable range from 8.45 mu m to 9.15 mu m . When the wavelength of the idler light was 8.84 mu m , the maximum output energy was 52.80 mu m , and the peak power was 6.60 kW. The novel tuning method offers an effective way to realize a tunable long-wave source for stand-off gas concentration detection.