论文标题
$ h $ bn中的双碳无效缺陷
Bistable carbon-vacancy defects in $h$-BN
论文作者
论文摘要
六角硼硝化硼中的单个光子发射器最近进行了广泛的研究。尽管对发射器的明确识别仍在激烈的研究中，但据信碳与碳相关的缺陷对于发射器的发射器起着至关重要的作用。在这项研究中，我们通过密度功能理论计算，系统地研究了碳胶外缺陷VNCB和CNVB的两种构型。我们计算了一个从一个缺陷到另一个缺陷的反应屏障能，以确定相对稳定性。我们发现屏障能量取决于电荷，CNVB可以在中性和正电荷状态下轻松地转换为VNCB，而在负电荷时稳定。地层能量计算表明，VNCB是CNVB上的主要缺陷。但是，VNCB和CNVB都没有合适的荧光光谱，可以再现观察到的荧光光谱。我们的结果表明，$ 1.6 $ -TO- $ 2.2 $ -EV发射器的起源应是其他与碳相关的配置。
Single photon emitters in hexagonal boron nitride have been extensively studied recently. Although unambiguous identification of the emitters is still under intense research, carbon related defects are believed to play a vital role for the emitter producing zero-phonon-lines in the range of $1.6$ to $2.2$~eV. In this study, we systematically investigate two configurations of carbon-vacancy defects, VNCB and CNVB, by means of density functional theory calculations. We calculated the reaction barrier energies from one defect to the other to determine relative stability. We find the barrier energies are charge dependent and CNVB could easily transform to VNCB in neutral and positive charge states while it is stable when negatively charged. Formation energy calculations show that the VNCB is the dominant defect over CNVB. However, neither VNCB nor CNVB has suitable fluorescence spectra that could reproduce the observed ones. Our results indicate that the origin of the $1.6$-to-$2.2$-eV emitters should be other carbon-related configurations.
