论文标题
观察磁性诱导的拓扑边缘状态在抗磁性拓扑绝缘子MNBI4TE7中
Observation of magnetism induced topological edge state in antiferromagnetic topological insulator MnBi4Te7
论文作者
论文摘要
拓扑绝缘子中的破坏时间逆转对称性可能会导致量子异常的霍尔效应和轴突绝缘子相。 MNBI4TE7是最近发现的具有Tn〜12.5 K的抗铁磁拓扑绝缘子，该绝缘子由替代磁层（MNBI2TE4）和非磁性层（BI2TE3）组成。通过扫描隧道光谱法，我们清楚地观察到磁性MNBI2TE4层的阶梯边缘存在的电子状态，但在4.5 K处的非磁性BI2TE3层处不存在，但随着温度的上升，温度上升到Edge State States的消失，而点降低了稳定的状态持续的温度持续下降。这些结果证实了磁性诱导的边缘状态的观察。我们基于轴突绝缘体理论的分析表明，观察到的边缘状态的非平凡拓扑性质。
Breaking time reversal symmetry in a topological insulator may lead to quantum anomalous Hall effect and axion insulator phase. MnBi4Te7 is a recently discovered antiferromagnetic topological insulator with TN ~12.5 K, which is constituted of alternatively stacked magnetic layer (MnBi2Te4) and non-magnetic layer (Bi2Te3). By means of scanning tunneling spectroscopy, we clearly observe the electronic state present at a step edge of a magnetic MnBi2Te4 layer but absent at non-magnetic Bi2Te3 layers at 4.5 K. Furthermore, we find that as the temperature rises above TN, the edge state vanishes, while the point defect induced state persists upon temperature increasing. These results confirm the observation of magnetism induced edge states. Our analysis based on an axion insulator theory reveals that the nontrivial topological nature of the observed edge state.
