论文标题
映射固有的反铁磁拓扑绝缘子（MNBI $ _2 $ te $ _4 $）（bi $ _2 $ _2 $ te $ _3 $）$ _ n $（n = 0，1）
Mapping the Dirac fermions in intrinsic antiferromagnetic topological insulators (MnBi$_2$Te$_4$)(Bi$_2$Te$_3$)$_n$ (n=0, 1)
论文作者
论文摘要
MNBI $ _2 $ TE $ _4 $（BI $ _2 $ te $ _3 $）$ _ N $化合物的拓扑表面状态已预计托管丰富的拓扑现象，包括量化的异常霍尔效应和轴心绝缘体状态。在这里，我们使用扫描隧道显微镜图像MNBI $ _2 $ TE $ _4 $和MNBI $ _4 $ TE $ te $ _7 $中的Surface Dirac Fermions成像。我们已经通过远远高于狄拉克能量的准粒子干扰模式确定了表面状态的能量分散和螺旋自旋纹理，这证实了其拓扑性质。在接近狄拉克点时，本地缺陷在MNBI $ _2 $ _4 $ _4 $ septuple层产生共振状态，它们在空间上且可能阻碍了光谱中的质量差距的检测。我们的结果表明，调节缺陷对于在这些化合物中较高温度下实现外来拓扑状态至关重要。
Topological surface states with intrinsic magnetic ordering in the MnBi$_2$Te$_4$(Bi$_2$Te$_3$)$_n$ compounds have been predicted to host rich topological phenomena including quantized anomalous Hall effect and axion insulator state. Here we use scanning tunneling microscopy to image the surface Dirac fermions in MnBi$_2$Te$_4$ and MnBi$_4$Te$_7$. We have determined the energy dispersion and helical spin texture of the surface states through quasiparticle interference patterns far above Dirac energy, which confirms its topological nature. Approaching the Dirac point, the native defects in the MnBi$_2$Te$_4$ septuple layer give rise to resonance states which extend spatially and potentially hinder the detection of a mass gap in the spectra. Our results demonstrate that regulating defects is essential to realize exotic topological states at higher temperatures in these compounds.
