用于PPLN泵浦源的大能量百纳秒级脉冲固体激光器

High-power Hundred-nanosecond Pulse Solid-state Laser for PPLN Pump Source

为获得大能量、百纳秒脉宽的1064 nm激光稳定输出,首先理论分析了激光的泵浦能量和谐振腔长度对输出脉宽的影响,然后对Nd∶YAG固体激光器进行设计,采用折叠谐振腔、振荡-放大结构和电光调Q技术相结合。实验结果表明:当重复频率为1 Hz、泵浦电压在1200~1400 V变化时,实现了脉宽范围为152.6~95.71 ns的稳定1064 nm激光输出,最大单脉冲能量可达171 mJ;以激光器的输出激光作为基频光,设计了柱透镜组光束耦合系统,将基频光光斑整形为椭圆形状,实现了基频光的高效耦合和周期极化LiNbO_(3)(PPLN)光参量振荡器的稳定运行;采用耦合后的光束泵浦MgO∶PPLN晶体,获得了1.47μm近红外信号光的稳定输出。

To achieve stable output of the 1064 nm laser with high energy and pulse width of hundred-nanosecond,the influence of laser pump energy and resonant cavity length of the laser on laser pulse width is theoretically analyzed.Then the Nd∶YAG solid-state laser is de-signed by using a combination of folded resonant cavity,oscillator-amplifier structure,and e-lectro-optic Q-switched technology.The experimental results indicate that:when the repeti-tion frequency is 1 Hz and the pump voltage changes between 1200 and 1400 V,the stable 1064 nm laser output is achieved with the pulse width range of 152.6~95.71 ns,and the maximum single pulse energy can be up to 171 mJ;with the output of the laser as the fundamental light,a cylindrical lens group beam coupling system is designed to shape the funda-mental light spot into an elliptical shape,which realizes the efficient coupling of the funda-mental light and stable function of the periodically polarized LiNbO_(3)(PPLN)optical para-metric oscillator;the stable output of 1.47μm near-infrared signal light is achieved by pum-ping MgO∶PPLN with the coupled beam.