论文标题
半磁性拓扑绝缘子
Half-Magnetic Topological Insulator
论文作者
论文摘要
拓扑磁铁是一种新的量子材料家族，具有实现新兴现象的巨大潜力，例如量子异常效应和轴突灭菌剂状态。在这里，我们发现的发现，具有天然异质结构MNBI2TE4-（BI2TE3）3是一种前所未有的半磁性绝缘体，具有天然异质结构的stoichiometric Ferromagnet Mnbi8te13，具有MNBI2TE4表面上的磁性化，但在相对的表面终止了Triple Biel Biel libi libi libi libi libi libi libi libies libies triple Biels lays layers agnetization。我们的角度分辨光发射光谱测量在MNBI2TE4表面揭示了巨大的狄拉克间隙，另一侧揭示了无间隙的狄拉克锥。值得注意的是，MNBI2TE4表面的Dirac Gap（〜28 MeV）随着温度的升高而单调地降低，并在Curie温度下关闭，从而代表了所有已知的磁性拓扑材料中磁化诱导的拓扑诱导拓扑表面隙的首次吸烟枪仪的光谱证据。从理论上讲，我们进一步证明了半磁性拓扑绝缘子需要实现半量化的表面异常霍尔效应，这可以直接证明凝结物质系统中轴突电动力学的一般概念。
Topological magnets are a new family of quantum materials providing great potential to realize emergent phenomena, such as quantum anomalous Hall effect and axion-insulator state. Here we present our discovery that stoichiometric ferromagnet MnBi8Te13 with natural heterostructure MnBi2Te4-(Bi2Te3)3 is an unprecedented half-magnetic topological insulator, with the magnetization existing at the MnBi2Te4 surface but not at the opposite surface terminated by triple Bi2Te3 layers. Our angle-resolved photoemission spectroscopy measurements unveil a massive Dirac gap at the MnBi2Te4 surface, and gapless Dirac cone on the other side. Remarkably, the Dirac gap (~28 meV) at MnBi2Te4 surface decreases monotonically with increasing temperature and closes right at the Curie temperature, thereby representing the first smoking-gun spectroscopic evidence of magnetization-induced topological surface gap among all known magnetic topological materials. We further demonstrate theoretically that the half-magnetic topological insulator is desirable to realize the half-quantized surface anomalous Hall effect, which serves as a direct proof of the general concept of axion electrodynamics in condensed matter systems.
