Sun Huacong, Yang Qing, Wang Jianlin, Ding Mingchao, Cheng Mouyang, Liao Lei, Cai Chen, Chen Zitao, Huang Xudan, Wang Zibing, Xu Zhi, Wang Wenlong, Liu Kaihui, Liu Lei, Bai Xuedong, Chen Ji, Meng Sheng, Wang Lifen
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China.
School of Physical Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China.
Nat Commun. 2024 Nov 2;15(1):9476. doi: 10.1038/s41467-024-53880-4.
Color centers, arising from zero-dimensional defects, exploit quantum confinement to access internal electron quantum degrees of freedom, holding potential for quantum technologies. Despite intensive research, the structural origin of many color centers remains elusive. In this study, we employ in-situ cathodoluminescence scanning transmission electron microscopy combined with integrated differential phase contrast imaging to examine how defect configuration in tungsten sulfide determines color-center emission. Using an 80-kV accelerated electron beam, defects were deliberately produced, visualized, excited in situ and characterized in real time in monolayer WS within hBN|WS | hBN heterostructures at 100 K. These color centers were simultaneously measured by cathodoluminescence microscopy and differentiated by machine learning. Supported by DFT calculations, our results identified a crucial sulfur vacancy configuration organized into featured vacancy pairs, generating stable and bright luminescence at 660 nm. These findings elucidate the atomic-level structure-exciton relationship of color centers, advancing our understanding and quantum applications of defects in 2D materials.
由零维缺陷产生的色心利用量子限制来获取内部电子量子自由度，具有量子技术潜力。尽管进行了深入研究，但许多色心的结构起源仍然难以捉摸。在本研究中，我们采用原位阴极发光扫描透射电子显微镜结合积分微分相衬成像，以研究硫化钨中的缺陷构型如何决定色心发射。使用80 kV加速电子束，在100 K下于hBN|WS | hBN异质结构中的单层WS中故意产生、可视化、原位激发并实时表征缺陷。这些色心通过阴极发光显微镜同时测量，并通过机器学习进行区分。在密度泛函理论计算的支持下，我们的结果确定了一种关键的硫空位构型，其组织成具有特征的空位对，在660 nm处产生稳定且明亮的发光。这些发现阐明了色心的原子级结构-激子关系，推动了我们对二维材料中缺陷的理解和量子应用。
