论文标题
抗位点缺陷诱导的疾病中的补偿拓扑磁铁MNBI $ _ {2-x} $ sb $ _x $ _x $ te $ _4 $
Anti-site defect-induced disorder in compensated topological magnet MnBi$_{2-x}$Sb$_x$Te$_4$
论文作者
论文摘要
补偿磁性拓扑绝缘子MNBI $ _ {2-x} $ sb $ _x $ _x $ te $ _4 $（MBST）的毛发状表面状态是外来量子现象的有前途的主机，例如量子异常霍尔霍尔霍姆效应和斧头绝缘状态。然而，很明显，原子缺陷破坏了量子相导致表面状态间隙和掺杂水平的空间变化的量子阶段的稳定。 MBST中大量可能的缺陷配置使研究单个缺陷的影响几乎是不可能的。在这里，我们通过扫描隧道显微镜/光谱法（STM/s）介绍了MBST中缺陷的纳米级效应的统计分析。我们将（BI，SB）$ _ {\ rm Mn} $抗位点缺陷作为观察到的掺杂波动的主要来源，导致形成纳米级电荷水坑并有效地缩小了传输缝隙。我们的发现将通过缺陷工程指导该材料系统的进一步优化，以实现其有希望的特性。
The gapped Dirac-like surface states of compensated magnetic topological insulator MnBi$_{2-x}$Sb$_x$Te$_4$ (MBST) are a promising host for exotic quantum phenomena such as the quantum anomalous Hall effect and axion insulating states. However, it has become clear that atomic defects undermine the stabilization of such quantum phases as they lead to spatial variations in the surface state gap and doping levels. The large number of possible defect configurations in MBST make studying the influence of individual defects virtually impossible. Here, we present a statistical analysis of the nanoscale effect of defects in MBST with $x=0.64$, by scanning tunneling microscopy/spectroscopy (STM/S). We identify (Bi,Sb)$_{\rm Mn}$ anti-site defects to be the main source of the observed doping fluctuations, leading towards the formation of nanoscale charge puddles and effectively closing the transport gap. Our findings will guide further optimization of this material system via defect engineering, to enable exploitation of its promising properties.
