周期极化掺镁铌酸锂晶体的光学参量振荡

Optical Parametric Oscillator Based on Periodically Poled MgO:LiNbO_3 Crystal

采用短脉冲极化电场法，在1mm厚的掺摩尔分数0．05镁的铌酸锂晶体上成功制备了周期为30μm的极化光栅。以输出波长为1．064μm的声光调QNd：YAG固体激光器作为基频抽运源对其进行了光学参量振荡实验，光参量振荡阈值功率为45mW（重复频率为1kHz），在输入功率为490mW，控温炉温度为160℃时，获得了94mW的波长为1544nm的信号光输出，转换效率达到19．2％。并且通过调谐晶体温度（20～180℃），获得了调谐范围为1503～1550nm的信号光稳定输出。实现了可调谐红外光的稳定输出，验证了晶体周期结构的均匀性。

By using short-pulse field, the periodically poled grating （A =30μm） was successfully fabricated in 1 mm thick MgO：LiNbO3 （doped 5 mol% MgO）. A high-repetition-rate optical parametric oscillator （OPO） experiment based on periodically poled MgO： LiNbO3 crystal （PPMgLN） pumped by a 1. 064 μm acousto-optically Q-switched Nd： YAG laser was performed. The threshold is 45 mW with 1 kHz pulse repetition rate. Under the condition of 490 mW of input pump power and at 160 ℃, 94 mW of output signal power was obtained, and the conversion efficiency is 19.2%. Furthermore a tunable infrared （IR） stable output from 1503 nm to 1550 nm was obtained by tuning the temperature of PPMgLN from 20 ℃ to 180 ℃.