High-repetition pulsed Nd:YVO4 laser based on the multi-longitudinal-mode beat note

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. (C) 2021 Society of Photo-Optical Instrumentation Engineers (SPIE)

Automated summary

Experimental results show that more longitudinal modes beating in the laser cavity lead to narrower laser pulse duration. Using an adjustable aperture in the laser cavity can weaken transverse mode interference and improve laser pulse train stability. By slightly tuning the Nd:YVO4 crystal temperature, a high-repetition laser pulse with 1.56 GHz and 0.18-ns time duration is achieved with certain output power and efficiency values.