van der Waals Heterostructures of 3D Topological Insulators and 2D Magnetic Materials

Three dimensional (3D) topological insulator (TI) based van der Waals heterostructures form an excellent platform to study the proximity effect between a TI surface and another layered material, such as a two-dimensional (2D) ferromagnet. Previously we have observed both massless relativistic Dirac fermions and massive (gapped) Dirac fermions in this way for the topological surface state of BiSbTeSe₂¹ and have reported quantum Hall data for these surfaces. However, typical ferromagnets get oxidized easily during the fabrication process. Thus, the induced magnetization in the TI interface is not clean under ambient conditions. To minimize the influence of oxidation, we explore this fabrication inside a glovebox. We will report the performance of such TI based devices in comparison to those built-in ambient conditions and further study the proximity effect in TI-based van der Waals heterostructures.


¹ Chong S et al 2018 Nano Lett. 18 8047