Li Song, Pershin Anton, Thiering Gergő, Udvarhelyi Péter, Gali Adam
Wigner Research Centre for Physics, P.O. Box 49, H-1525 Budapest, Hungary.
Department of Atomic Physics, Institute of Physics, Budapest University of Technology and Economics, Müegyetem rakpart 3, H-1111 Budapest, Hungary.
J Phys Chem Lett. 2022 Apr 14;13(14):3150-3157. doi: 10.1021/acs.jpclett.2c00665. Epub 2022 Apr 1.
Ultraviolet (UV) quantum emitters in hexagonal boron nitride (hBN) have generated considerable interest due to their outstanding optical response. Recent experiments have identified a carbon impurity as a possible source of UV single-photon emission. Here, on the basis of first-principles calculations, we systematically evaluate the ability of substitutional carbon defects to develop the UV color centers in hBN. Of 17 defect configurations under consideration, we particularly emphasize the carbon ring defect (6C), for which the calculated zero-phonon line agrees well the experimental 4.1 eV emission signal. We also compare the optical properties of 6C with those of other relevant defects, thereby outlining the key differences in the emission mechanism. Our findings provide new insights into the strong response of this color center to external perturbations and pave the way to a robust identification of the particular carbon substitutional defects by spectroscopic methods.
六方氮化硼（hBN）中的紫外（UV）量子发射器因其出色的光学响应而引起了广泛关注。最近的实验已确定碳杂质可能是紫外单光子发射的来源。在此，基于第一性原理计算，我们系统地评估了替代碳缺陷在hBN中形成紫外色心的能力。在所考虑的17种缺陷构型中，我们特别强调了碳环缺陷（6C），其计算出的零声子线与实验测得的4.1 eV发射信号吻合良好。我们还将6C的光学性质与其他相关缺陷的光学性质进行了比较，从而概述了发射机制中的关键差异。我们的研究结果为深入了解该色心对外部扰动的强烈响应提供了新的见解，并为通过光谱方法可靠识别特定的碳替代缺陷铺平了道路。
