Magnetic proximity and nonreciprocal current switching in a monolayer WTe2 helical edge
Magnetic proximity and nonreciprocal current switching in a monolayer WTe2 helical edge
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DOI：
10.1038/s41563-020-0620-0
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发表时间：
2020-01
期刊：
影响因子：
41.2
通讯作者：
Wenjin Zhao;Z. Fei;Tiancheng Song;Han Kyou Choi;T. Palomaki;Bosong Sun;P. Malinowski;M. McGuire;J. Chu;Xiaodong Xu;D. Cobden
中科院分区：
文献类型：
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作者：
Wenjin Zhao;Z. Fei;Tiancheng Song;Han Kyou Choi;T. Palomaki;Bosong Sun;P. Malinowski;M. McGuire;J. Chu;Xiaodong Xu;D. Cobden
将多种电子现象（如磁性和非平凡拓扑）集成到一个单一系统中，通常是通过寻找包含这两种成分的材料或通过对比材料的分层生长，，，，，，，-来研究的。简单地将非常不同的二维范德华材料紧密接触堆叠在一起的能力允许了一种不同的方法。在这里，我们使用这种方法来耦合二维拓扑绝缘体的螺旋边缘状态，单层WTe2（参考文献）。，，， -)，到二维层状反铁磁体CrI3（参考文献）。我们发现边缘电导对CrI3的磁化状态很敏感，这种耦合可以用最近和次近的CrI3层的交换场来理解，交换场会在螺旋边缘产生间隙。我们还发现，非线性边缘电导取决于最近的cri3层相对于电流方向的磁化强度。在低温下，通过改变CrI3的反铁磁状态，可以产生非常大的非互易电流。
The integration of diverse electronic phenomena, such as magnetism and nontrivial topology, into a single system is normally studied either by seeking materials that contain both ingredients, or by layered growth of contrasting materials, , , , , , , –. The ability to simply stack very different two-dimensional van der Waals materials in intimate contact permits a different approach,. Here we use this approach to couple the helical edges states in a two-dimensional topological insulator, monolayer WTe2(refs., , , –), to a two-dimensional layered antiferromagnet, CrI3(ref. ). We find that the edge conductance is sensitive to the magnetization state of the CrI3, and the coupling can be understood in terms of an exchange field from the nearest and next-nearest CrI3layers that produces a gap in the helical edge. We also find that the nonlinear edge conductance depends on the magnetization of the nearest CrI3layer relative to the current direction. At low temperatures this produces an extraordinarily large nonreciprocal current that is switched by changing the antiferromagnetic state of the CrI3.