绿光抽运准周期光学超晶格产生红光与蓝光的研究

Generation of Red and Blue Laser from Green Pump Laser in Quasi-Periodic Optical Superlattice

使用一块准周期LiTaO3 光学超晶格晶体 ,利用准相位匹配技术 ,通过光参变产生与和频两个非线性过程 ,将一束 5 32nm绿色抽运光转变成 6 6 6nm红光与 4 4 3nm蓝光。具体过程为 ,通过参变过程获得红色信号光和红外闲频光 ,再通过绿色抽运光与红外闲置光和频获得蓝光 ,两个过程在同一块准周期光学超晶格中实现 ,准周期超晶格的两个倒易矢量分别补偿这两个过程中的相位失配。抽运光的脉宽为 4 0ps ,重复频率为 10Hz,在平均功率为 0 .5mW时 ,测得红光和蓝光功率分别 0 .15mW和 16 .6 μW ,转换效率达到 34%和 3%。这一方法 ,提供了一种用一块超晶格晶体同时获得三原色输出的有效途径。

The red light at 666 nm and the blue light at 443 nm are obtained simultaneously by quasi-phase matching from a quasi-periodic LiTaO 3 optical superlattice using a ps 532 nm laser as a pump through two cascaded nonlinear processes, a quasi-phase matched parametric generation and a quasi-phase matched sum-frequency process. In detail, the former process is used to get the red signal and the infrared idle light, meanwhile, the latter is to get the blue light by the sum of the pump and idle light. The two processes are phase-matched by two reciprocal vectors of the same optical superlattice. The pump's pulse width is 40 ps with a repetition of 10 Hz. The power of the red light is 0.15 mW and the blue 16.6 μW under the average pump power of 0.5 mW, corresponding to the conversion efficiency of 34.0% and 3% respectively. The result shows a new technical approach to obtain three primary colors.