报道了一台平均功率3.09 W、和频效率大于35%的周期极化化学计量比钽酸锂(PPSLT)晶体准相位匹配和频钠导星激光器。用声光调Q的二极管抽运Nd:YAG固体激光器产生高光束质量的基频光1064 nm与1319 nm,在腔内插入高精度控温的标准具获得窄线宽输出,并在腔外通过准相位匹配的PPSLT晶体和频产生钠导星激光。当注入PPSLT晶体的1064 nm和1319 nm总平均功率约8.80 W时,在匹配温度68 ℃时实现了最高和频转换,输出钠导星激光3.09 W,重复频率800 Hz,脉宽约60 ns,线宽约1.6 GHz。并通过调节控制标准具的倾斜角度和温度,将中心波长对准至钠D2a线589.1591 nm,偏差小于±0.2 pm。

A 3.09 W sodium guidestar laser with the sum frequency generation efficiency more than 35% is reported.The laser is based on the periodically poled stoichiometric lithium tantalite(PPSLT) crystal quasi-phase-matched sum frequency generation.Two acousto-optical (AO) Q-switched diode pumped Nd:YAG lasers of 1064 nm and 1319 nm are used as the fundamental-frequency lasers.To get the narrow linewidth output,the etalons with well temperature controlling are inserted into the cavities.The sodium guidestar laser is generated through an external-cavity quasi-phase-matched sum frequency PPSLT crystal.When the total power of 1064 nm and 1319 nm is 8.80 W,the output sodium guidestar laser′s power is 3.09 W with the highest sum frequency generation efficiency at the matching temperature of 68 ℃.The repetition frequency of the laser is 800 Hz and the width of pulse is about 60 ns.The linewidth is about 1.6 GHz.The central wavelength is locked to sodium D2a line 589.1591 nm (error less than ±0.2 pm) by tuning the angle and the temperature of the etalons.