Tunable Topological Phase Transition in 2D Heterostructures

Two dimensional (2D) materials can host a wide range of properties, such as magnetism [1], high mobility and a wide range of topological properties [2]. Recently, it has been experimentally shown that heterostructures of 2D materials can be synthesized. This leads to the exciting possibility of interfacing 2D materials in heterostructure geometries to design new and exotic quantum-materials for dissipationless quantum-transport. In this study, we theoretically demonstrate that vertical heterostructures of magnetic and topological 2D materials can give rise to quantum anomalous Hall (QAH) effect. In addition, we show that electric-fields can be used to tune the interfacial coupling to drive the system to the QAH regime. We demonstrate this concept in 2D heterostructures such as CrI₃/Sb/CrI₃, CrI₃/Si/CrI₃, and CrI₃/Ge/CrI₃.
[1] B. Huang et al., Nature 546, 270 (2017).
[2] L. Kou et al., J. Phys. Chem. Lett. 8, 1905 (2017).