论文标题
3D拓扑绝缘子/2D磁铁范德华异质结构
Gate-tunable anomalous Hall effect in a 3D topological insulator/2D magnet van der Waals heterostructure
论文作者
论文摘要
我们证明了通过与相邻磁铁层相互作用的3维拓扑绝缘子（TI）来控制3维拓扑绝缘子（TI）的拓扑表面状态的样品的优势。我们使用Ti Bisbtese2和磁铁CR2GE2TE6的去角质片剂组装了双层界面，从而避免了由散射引起的问题，该问题可能影响由自上而下的沉积方法产生的接口。样品表现出异常的大厅效应（AHE），并突然滞后。首次在由Ti和单独的铁磁层组成的样品中，我们证明了AHE的振幅可以通过栅极电压调节，在DIRAC点附近具有强峰。这是由于与拓扑表面状态与面积非平面磁体之间相互作用引起的交换差距相关的浆果曲率引起的AHE的签名。
We demonstrate advantages of samples made by mechanical stacking of exfoliated van der Waals materials for controlling the topological surface state of a 3-dimensional topological insulator (TI) via interaction with an adjacent magnet layer. We assemble bilayers with pristine interfaces using exfoliated flakes of the TI BiSbTeSe2 and the magnet Cr2Ge2Te6, thereby avoiding problems caused by interdiffusion that can affect interfaces made by top-down deposition methods. The samples exhibit an anomalous Hall effect (AHE) with abrupt hysteretic switching. For the first time in samples composed of a TI and a separate ferromagnetic layer, we demonstrate that the amplitude of the AHE can be tuned via gate voltage with a strong peak near the Dirac point. This is the signature expected for the AHE due to Berry curvature associated with an exchange gap induced by interaction between the topological surface state and an out-of-plane-oriented magnet.
