近日，华南理工大学的夏志国及其研究团队取得一项新进展。经过不懈努力，他们研制出具有瓦级输出的激光驱动宽带近红外光源。相关研究成果已于2024年3月1日在国际知名学术期刊《自然—光子学》上发表。
本文报道了一种火花等离子烧结制备的MgO:Cr3+半透明陶瓷，该陶瓷在810nm处具有宽带近红外发射峰，外量子效率为81%，超高导热系数为52Wm-1K-1。当用蓝色激光泵浦时，MgO:Cr3+陶瓷提供超过6W的输出功率，电光转换效率为29%。这种激光驱动的宽带近红外光源使得以6lpmm-1的空间分辨率进行近红外成像成为可能，是新兴成像应用的一项有前途的技术。
据悉，基于激光激发荧光粉的大功率宽带近红外(NIR)光源在夜视、生物医学成像和传感领域的光子学应用是非常理想的; 然而，固有的能隙定律给高效近红外发光材料的开发带来了很大的挑战。
附：英文原文
Title: Laser-driven broadband near-infrared light source with watt-level output
Author: Liu, Gaochao, Chen, Weibin, Xiong, Zhan, Wang, Yuzhen, Zhang, Shuai, Xia, Zhiguo
Issue&Volume: 2024-03-01
Abstract: 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 810nm, with an external quantum efficiency of 81% and ultra-high thermal conductivity of 52Wm–1K–1. When pumped with a blue laser, the MgO:Cr3+ ceramic provides an output power exceeding 6W 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 6lpmm–1, and is a promising technology for emerging imaging applications.
DOI: 10.1038/s41566-024-01400-7
Source: https://www.nature.com/articles/s41566-024-01400-7