采用连续Nd:YVO4 激光器作为泵浦源, 在室温下实现了PPMgLN晶体准相位匹配, 获得了连续内腔光学参量振荡。获得的光参量阈值仅为3 W (808 nm); 在泵浦光功率为5 W、PPMgLN极化周期为31.5 m时, 获得了365 mW、2.95 m的中红外连续激光输出和312 mW、1.66 m信号光输出, 总光光转换效率达到13.3%。通过改变晶体周期, 实现了2.95?4.16 m闲频光和1.43?1.66 m信号光的宽带可调谐输出。此连续中红外光参量振荡器结构简单紧凑, 效率高, 将是未来产生3?5 m中红外激光光源的重要方法之一。

By using a continuous wave (CW) Nd:YVO4 laser as the pump source, the quasi-phase match is implemented for a PPMgLN crystal at room temperature and a continuous intracavity optical parametric oscillator (OPO) is obtained. The optical parametric threshold obtained is only 3 W (808 nm). For the pump power of 5 W and the period of PPMgLN crystal of 31.5 m, both continuous mid-infrared laser output with the power of 365 mW at the wavelength of 2.95 m and the signal laser output with the power of 312 mW at the wavelength of 1.66 m are obtained. The total light conversion efficiency is up to 13.3%. By changing the periods of the crystal, the wide band tunable output of idle light in the spectral range from 2.95 m to 4.16 m and that of the signal light in the spectral range from 1.43 m to 1.66 m are obtained. This mid-infrared optical parametric oscillator is simple in structure and high in efficiency. It will be one of the important methods for producing 3-5 m mid-infrared laser sources in the future.