Laser-driven broadband near-infrared light source with watt-level output

作者：Liu, Gaochao; Chen, Weibin; Xiong, Zhan; Wang, Yuzhen; Zhang, Shuai; Xia, Zhiguo^*

来源：Nature Photonics, 2024.

DOI：10.1038/s41566-024-01400-7

• HIGHLY EFFICIENT
• SUBSTITUTION
• LUMINESCENCE
• GARNET
• MGO

High-power broadband near-infrared (NIR) light sources based on laser-excited phosphors are highly desirable for photonics applications in night vision, biomedical imaging and sensing; however, the inherent energy gap law poses a great challenge for the development of efficient NIR luminescent materials. Herein we report a translucent MgO:Cr3+ ceramic fabricated by spark plasma sintering, which exhibits a broadband NIR emission peak at 810 nm, with an external quantum efficiency of 81% and ultra-high thermal conductivity of 52 W m-1 K-1. When pumped with a blue laser, the MgO:Cr3+ ceramic provides an output power exceeding 6 W with an electro-optical conversion efficiency of 29%. This laser-driven broadband NIR light source makes it possible to perform NIR imaging with a spatial resolution of 6 lp mm-1, and is a promising technology for emerging imaging applications. @@@ A transparent ceramic phosphor based on Cr3+-doped MgO offers a route to a powerful broadband near-infrared light source.