论文标题
设计磁性拓扑范德华异质结构
Designing Magnetic Topological van der Waals Heterostructure
论文作者
论文摘要
我们通过结合2D磁铁CRI $ _3 $ _3 $和2D材料（GE/SB）来实现新的2D拓扑系统与非零CHERN数字（C = 1）和chiral Edge，来利用VDW异质结构（VDW-HS）来设计2D功能磁性拓扑异质结构（HS）的新方法。非平凡拓扑主要起源于CRI $ _3 $层，而非磁性元件诱导电荷传输过程和接近性增强的自旋轨道耦合。由于这些独特的特性，我们的拓扑磁VDW-HS通过以前的设计中的接近效应克服了弱磁化，因为磁化和拓扑在同一磁层中共存。具体而言，我们的双层CRI $ _3 $/sb和Trilayer CRI $ _3 $ _3 $/sb/cri $ _3 $的系统表现出不同的拓扑结构状态，范围从抗Fiferromagnetic拓扑结晶绝缘子（C $ _M $ = 2）到QAHE。由于在存在外部垂直电场的情况下，这些非平凡的拓扑转变被证明是在三层构造中可切换的，因此从防铁磁性转变为铁触者。因此，我们的研究提出了一个现实的系统，以设计具有电场的可切换磁性拓扑设备。
We demonstrate a new method of designing 2D functional magnetic topological heterostructure (HS) by exploiting the vdw heterostructure (vdw-HS) through combining 2D magnet CrI$_3$ and 2D materials (Ge/Sb) to realize new 2D topological system with nonzero Chern number (C=1) and chiral edge state. The nontrivial topology originates primarily from the CrI$_3$ layer while the non-magnetic element induces the charge transfer process and proximity enhanced spin-orbit coupling. Due to these unique properties, our topological magnetic vdw-HS overcomes the weak magnetization via proximity effect in previous designs since the magnetization and topology coexist in the same magnetic layer. Specifically, our systems of bilayer CrI$_3$/Sb and trilayer CrI$_3$/Sb/CrI$_3$ exhibit different topological ground state ranging from antiferromagnetic topological crystalline insulator (C$_M$= 2) to a QAHE. These nontrivial topological transition is shown to be switchable in a trilayer configuration due to the magnetic switching from antiferromagnetism to ferromangetism in the presence an external perpendicular electric field with value as small as 0.05 eV/A. Thus our study proposes a realistic system to design switchable magnetic topological device with electric field.
