A high-repetition pulsed Nd : YVO4 laser based on the multi-longitudinal-mode beat note is presented. The mechanism of multi-mode oscillating in the Nd : YVO4 laser with FP cavity is analyzed. With the multi-mode Nd : YVO4 laser in experiments, it is found that the more longitudinal modes beating in the laser cavity, the narrower time duration of the laser pulse is obtained. An adjustable aperture is employed in the laser cavity to weaken the transverse mode interference and improve the laser pulse train stability. At last, when the FP laser cavity length is 88 mm, by slight tuning the Nd : YVO4 crystal temperature, a 1.56 GHz high-repetition laser pulse with 0.18-ns time duration is achieved. The average output power of the pulse train is 1605 mW with the pump power at 6788 mW. The slope efficiency and the optical-to-optical efficiency are calculated as 31% and 24%, respectively.

中文翻译：

---

基于多纵模拍音的高重复脉冲 Nd:YVO ₄激光器

提出了一种基于多纵模拍音的高重复脉冲 Nd : YVO4 激光器。分析了FP腔Nd:YVO4激光器的多模振荡机理。实验中采用多模Nd：YVO4激光器，发现在激光腔内跳动的纵模越多，获得的激光脉冲持续时间越短。激光腔内采用可调孔径来减弱横模干涉，提高激光脉冲串的稳定性。最后，当FP激光腔长为88 mm时，通过微调Nd : YVO4晶体温度，获得1.56 GHz高重复脉冲，持续时间为0.18 ns。脉冲串的平均输出功率为 1605 mW，泵浦功率为 6788 mW。