Widely tunable and high resolution mid-infrared laser based on optical parametric oscillator

Phys.org  October 18, 2023
A widely tunable and high resolution mid-infrared radiation source operating in the 3–5 µm region has been applied to numerous frontier applications. However, due to the narrow absorption peak linewidth of atmospheric molecules, it is necessary to strictly align the output wavelength with the target wavelength, which requires high wavelength resolution. Researchers in China tuned the temperature and angle of BaGa4Se7 (BGSe) crystals simultaneously placing the crystals in a temperature-controlled furnace, and placed the furnace on an electric rotary platform. This scheme achieved both wide-range wavelength tuning and high-resolution wavelength tuning with stable output wavelength. It overcame the problem of BGSe OPO output wavelength shifts with changes in ambient temperature. The wavelength tuning resolution was 0.3 nm, and the output wavelength was stable. According to the researchers the output wavelength range of high-resolution can be expanded to 2.7 μm–17 μm by replacing the BGSe crystals… read more. TECHNICAL ARTICLE 

Credit: Front. Optoelectron. 16, 26 (2023)