全固态单纵模593.5 nm和频激光器

利用法布里-珀罗(F-P)标准具选频实现了单纵模593.5 nm激光和频输出。采用单块Nd:YVO₄晶体,通过对谐振腔输出镜膜系的设计与优化,在两镜线性腔中实现了稳定的1 064 nm与1 342 nm双波长振荡。放入I类位相匹配和频晶体LBO进行腔内和频时,抽运功率为2 W可获得52 mW的593.5 nm橙黄色激光输出,但输出光束噪声较大,其RMS噪声为6.8%。在腔内加入400 μm厚熔融石英标准具进行选频,实现了单纵模593.5 nm激光输出,单纵模线宽为600 MHz,输出功率为34 mW,RMS噪声降为0.3%,实现了低噪声输出。实验结果表明,在和频过程中,利用一块标准具对两个波长同时进行选频是获得单纵模和频光的有效方法。

All-solid-state single-longitudinal-mode 593.5 nm sum-frequency laser

A single-longitudinal-mode sum-frequency 593.5 nm laser was developed using a Fabry-Perot etalon as the frequency selector. For a single Nd:YVO₄ crystal, stable dual-wavelength operation of 1 064 nm and 1 342 nm was obtained in a linear cavity by optimally designing the films on the output mirror of a cavity. The sum-frequency generation was realized using a type-I phase-matching LBO crystal for the sum-frequency mixing of 1 064 nm and 1 342 nm. Under the pump power of 2 W, 52 mW yellow-orange light at 593.5 nm was generated with a RMS noise of 6.8%. Then a 400 μm thick fused quartz was inserted into the cavity for frequency selection, 34 mW single-longitudinal-mode light with a linewidth of about 600 MHz at 593.5 nm was obtained by tuning the tilt angle of the etalon. The noise of the output light was remarkably reduced to the RMS noise of 0.3%. The results show that it is an easy and efficient way to employ a single Fabry-Perot etalon as the frequency selector to obtain single-longitudinal operation of the sum-frequency light in the process of sum-frequency generation.