High Repetition Rate, Tunable Mid-Infrared BaGa4Se7 Optical Parametric Oscillator Pumped by a 1 μm Nd:YAG Laser

A tunable and compact mid-infrared optical parametric oscillator (OPO) based on BaGa4Se7 (BGSe) crystal with a repetition rate up to 250 Hz was demonstrated. A high energy and more approachable side-pumped Q-switched Nd:YAG laser was employed as the pump for the BGSe OPO. Due to the pump double-pass single-resonant oscillator (DP-SRO) configuration, the maximum average power of 250 mW and the maximum pulse energy of 1.28 mJ at 4.06 mu m was achieved with the repetition rate of 250 Hz and 100 Hz, respectively. The tunable mid-infrared output from 3.42-4.73 mu m was obtained. The influence of repetition rate and cavity length was studied and the thermal effect was analyzed.

Automated summary

This study demonstrated a tunable mid-infrared optical parametric oscillator based on BGSe crystal, using a high energy side-pumped Nd:YAG laser as the pump source, achieving a maximum average power of 250 mW and maximum pulse energy of 1.28 mJ at 4.06 μm. Tunable mid-infrared output from 3.42-4.73 μm was obtained, and the effects of repetition rate and cavity length on the system performance were studied.