Huang Hsin-Jia, Chang Xiu-Wei, Hsieh Cheng-Li, Li Di, Chen Yung-Fu
Opt Express. 2024 Apr 8;32(8):14133-14142. doi: 10.1364/OE.520582.
Compact efficient high-power continuous-wave Nd:YVO Raman lasers for selectable wavelengths within 559-603 nm are achieved by using KGW crystal for intracavity stimulated Raman scattering (SRS) and lithium triborate (LBO) crystal for intracavity sum frequency generation (SFG) and second harmonic generation (SHG). The LBO crystal with the cut angle in the XY plane for the type-I phase matching is used to perform intracavity SHG or SFG. Experimental results reveal that the participated Stokes lines include the internal vibration mode at 901 cm, the external vibrational mode at 209 cm, and the combination mode of the 901 cm and 209 cm Raman shifts. By tuning LBO temperature for attaining the maximum output power, the output spectrum reveals the triple peaks of 588.7, 595.7, and 603.1 nm with the intensity ratio of 10:4:1. Under this circumstance, the output power can reach the highest value of 10.8 W at a pump power of 40 W. Furthermore, the output spectrum can be simply concentrated on the single peaks among 588.7 (orange), 565.7 (yellow), and 559.1 nm (lime) by tuning LBO temperature to fulfill the selection of the critical phase matching. The output powers at a pump power of 40 W can be up to 8.0, 6.1, and 9.8 W for the single-peak emission at 588.7, 565.7, and 559.1 nm, respectively. Finally, a dual-peak emission of 565.7 and 572.3 nm with total output power of 5.2 W can be generated by tuning LBO temperature to match the SFG for 572.3 nm.
通过使用KGW晶体进行腔内受激拉曼散射（SRS）以及使用硼酸三锂（LBO）晶体进行腔内和频产生（SFG）与二次谐波产生（SHG），实现了紧凑高效的高功率连续波Nd:YVO拉曼激光器，其波长可在559 - 603 nm范围内选择。具有XY平面内I型相位匹配切割角的LBO晶体用于执行腔内SHG或SFG。实验结果表明，参与的斯托克斯线包括901 cm处的内部振动模式、209 cm处的外部振动模式以及901 cm和209 cm拉曼位移的组合模式。通过调节LBO温度以获得最大输出功率，输出光谱显示出588.7、595.7和603.1 nm的三峰，强度比为10:4:1。在这种情况下，泵浦功率为40 W时，输出功率可达到最高值10.8 W。此外，通过调节LBO温度以实现临界相位匹配的选择，输出光谱可简单地集中在588.7（橙色）、565.7（黄色）和559.1 nm（柠檬绿）的单峰上。泵浦功率为40 W时，588.7、565.7和559.1 nm单峰发射的输出功率分别可达8.0、6.1和9.8 W。最后，通过调节LBO温度以匹配572.3 nm的SFG，可产生565.7和572.3 nm的双峰发射，总输出功率为5.2 W。
