Chinese Optics Letters, Vol. 17, Issue 12, 121402 (2019)
A compact and efficient 4.25 μm BaGa4Se7 optical parametric oscillator
Minqiang Kang1, Ying Deng1,2,3, Xiongwei Yan1, Xiaoming Zeng1,2,3, Yangwu Guo4, Jiyong Yao4,*, Fa Zeng1, Jiangang Zheng1,2,3, Kainan Zhou1,2,3, Chongbing Qu5, Jingqin Su1,2,3, and Qihua Zhu1,2,3,**

Author Affiliations

- 1Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900, China
- 2Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240, China
- 3Science and Technology on Plasma Physics Laboratory, Mianyang 621900, China
- 4Center for Crystal Research and Development, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- 5Graduate School of China Academy of Engineering Physics, Beijing 100088, China
Abstract
We report an efficient mid-infrared extracavity optical parametric oscillator (OPO) based on the nonlinear crystal BaGa4Se7 pumped by a diode-side-pumped Q-switched Nd:Y3Al5O12 (Nd:YAG) laser. The maximum pulse energy of 1.03 mJ at 4.25 μm is obtained with the repetition rate of 10 Hz and pulse width of 12.6 ns when the pump energy was 13.5 mJ, corresponding to an optical-to-optical conversion efficiency of 7.6% from 1.064 μm to 4.25 μm. The idler wave slope conversion efficiency was 12%. To the best of our knowledge, it is the highest reported conversion efficiency for the compact BaGa4Se7 OPO driven by the Nd:YAG laser.