波长锁定878.9nm激光二极管抽运内腔式YVO_4/BaWO_4连续波拉曼激光器

采用波长锁定878.9 nm激光二极管共振抽运复合Nd:YV04激光晶体,改善热效应的同时提高抽运吸收率,分别以YVO_4和BaWO_4晶体作为拉曼介质,实验和理论研究了晶体性能、谐振腔结构和稳定性对内腔分体式连续波拉曼激光器性能的影响.结果表明:由于内腔分体式拉曼激光器腔长较长,谐振腔稳定性对激光器性能影响较大,选择高增益的拉曼晶体,不仅可获得高拉曼转换效率,还能一定程度上减轻热效应.而平凹腔结构中输出镜的曲率半径越小,拉曼晶体中基频光的功率密度越大,腔的动态稳定区越宽,获得的拉曼激光输出功率更高.最终以30 mm的BaWO_4晶体作为拉曼介质,在抽运功率25.1 W时,获得了3.02 W的连续拉曼激光输出,光-光转换效率达到12%.     

Investigation of magneto-optical effect in transverse magnetic field in He

The non-linear Voigt effect has been studied in He discharge under resonance laser interaction with the He transition. The range of non-linear signal existence was determined. The contribution of the lower and upper states to the overall signal was analyzed. The cross-section for depolarizing collisions with ground state He atoms was estimated for the 3³ D _2,3 He state. Received: 16 June 1998 / Received in final form: 14 December 1998     

Generation of coherent blue light via bichromatic pumping in cesium vapor

Diode-pumped alkali lasers, possessing high efficiency and narrow linewidth, can provide feasible solutions for wavelength ranges difficult to reach by commercial lasers. In this study, we investigate a generation of coherent blue light (CBL) via four-wave mixing (FWM)-based up-conversion processes in cesium (Cs) vapor. A bichromatic pumping scheme with 852- and 917-nm lasers drives the Cs atoms to the 6D_5/2 excited level, followed by cascaded decay of 6D_5/2 → 7P_3/2 → 6S_1/2, producing 456-nm CBL under phase matching conditions. The fluorescence in multiple bands from blue to near- and far-infrared in the FWM process is demonstrated under different experimental conditions. To optimize the experimental parameters, we investigate the dependence of 456-nm CBL on the vapor temperature, frequency, and intensity of the two pump lasers. A maximum power of 2.94 mW is achieved with pump powers of 430 mW (for 852 nm) and 470 mW (for 917 nm). The corresponding conversion efficiency is 1.5%/W, three-fold higher than those in previous studies. Our results can contribute to fundamental research on atom−photon interactions and quantum metrology.