1.9 µm laser pumped PPMgLN mid-infrared optical parametric oscillator

完成了采用波长为1.9 µm的 Tm:YLF脉冲激光器泵浦周期极化晶体PPMgLN的光学参量振荡器的实验。并通过采用两种掺杂浓度不同的Tm:YLF晶体建立的激光器作为PPMgLN光学参量振荡器的泵浦源，分别研究了光学参量振荡器的性能。采用掺杂MgO浓度为5%的周期长度为30.5 µm的单周期结构的晶体PPMgLN作为光学参量振荡器的非线性晶体，在采用输出镜为50%的情况下，得到的光学参量振荡器的输出信号光和空闲光的总的最高功率为900 mW，对应的输出功率增长的斜率效率为70%。在1.9 µm泵浦光的功率超过阈值3.2倍时，得到的中红外激光的功率转换效率达到了31%。The experiment of 1.9 µm Tm:YLF laser pumping PPMgLN OPO is accomplished. Properties of PPMgLN OPO is investigated by using two pump source with different Tm:YLF dopant concentration. PPLN with single period of 30.5 µm and doped with 5% MgO served as the nonlinear crystal, with a OC of 50% reflectivity, the maximal output power of total signal and idler is 900 mW, and the power efficiency is 70%. The power conversion efficiency reaches 31% when the 1.9 µm pump power is 3.2 times above the threshold