Intracavity-Pumped, Mid-Infrared Tandem Optical Parametric Oscillator Based on BaGa4Se7 Crystal

• Published in: IEEE photonics journal 2019-12, Vol.11 (6), p.1-9
• Main Authors: He, Yixin, Zhong, Kai, Wu, Yicheng, Yao, Jianquan, Xu, Degang, Yao, Jiyong, Wang, Yuye, Guo, Yangwu, Zhu, Xianli, Yan, Chao, Tang, Longhuang, Li, Jining
• Format: Article
• Language: English
• Subjects: Crystals; Nonlinear crystals (<named-content xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" content-type="math" xlink:type="simple"> <inline-formula> <tex-math notation="LaTeX"> text{BaGa}_4 \text{ Se}_7</tex-math> </inline-formula> </named-content> crystal); Nonlinear crystals (<named-content xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" content-type="math" xlink:type="simple"> <tex-math notation="LaTeX">$\text{BaGa}_4 \text{ Se}_7$</tex-math> </named-content> crystal); Nonlinear optics; optical parametric oscillator; Optical Parametric Oscillators; Optical pumping; Oscillators; Parametric amplifiers; Phase matching; Photonic crystals; Potassium titanyl orthophosphate; Quantum cascade lasers; tunable mid-infrared source; Tuning
• ISSN: 1943-0655; 1943-0647
• DOI: 10.1109/JPHOT.2019.2953097

We have demonstrated a tunable mid-infrared tandem optical parametric oscillator (OPO) based on BaGa4Se7 (BGSe) crystal, which was intracavity-pumped by the tunable signal wave at ~1 μm generated from a KTiOPO4-OPO (KTP-OPO) in doubly-resonant oscillator (DRO) configuration. Wavelength tuning of the mid-infrared tandem OPO was realized by tuning the pump wavelength at the fixed phase matching angle to reduce the effects of beam cutting and Fresnel reflection loss. Together with pump-tuning method, angle-tuning method was supplied to extend tuning range. A tuning range of 4.1-4.5 μm was obtained with just 5 individual phase matching angles of the BGSe crystal. The maximum output energy of 1.92 mJ/pulse was obtained at 4.26 μm with an estimated slope efficiency of 9.5%.