Department of Electronic Engineering, Ming Chuan University, Taoyuan, Taiwan.
Opt Lett. 2010 Jan 15;35(2):160-2. doi: 10.1364/OL.35.000160.
We report a design for upconversion 435 nm blue lasers based on simultaneously fulfilling the nonlinear processes of optical parametric oscillation (OPO) and second-harmonic generation (SHG) in a 7.9 mum periodically poled lithium tantalate (PPLT). The uncoated 15-mm-long PPLT device exhibits a low threshold of 150 mW and a differential slope efficiency of 22.6%, rendering 56 mW blue generation when pumped by a pulsed 532 nm green laser with an average power rating of 400 mW. These observations were attributed to a quasi-phase-matching (QPM) structural design with a 75% domain duty cycle to ensure the concurrence of frequency doubling with the first-order QPM-OPO PPLT device via the second-order QPM-SHG process.
我们报告了一种基于同时满足光学参量振荡（OPO）和二次谐波产生（SHG）的非线性过程的 7.9 µm 周期极化钽酸锂（PPLT）上转换 435nm 蓝光激光器的设计。未镀膜的 15mm 长 PPLT 器件具有 150mW 的低阈值和 22.6%的微分斜率效率，当用平均功率为 400mW 的脉冲 532nm 绿光泵浦时，可产生 56mW 的蓝光。这些观察结果归因于具有 75%的域占空比的准相位匹配（QPM）结构设计，以确保通过二阶 QPM-SHG 过程与一阶 QPM-OPO PPLT 器件同时发生倍频。
