Magnetize Topological Surface States of Bi2Se3 with a CrI3 Monolayer

TL;DR

This study demonstrates that a CrI3 monolayer can induce magnetic properties in Bi2Se3 topological insulators without damaging their surface states, paving the way for high-temperature quantum anomalous Hall effect applications.

Contribution

It reveals that a CrI3 monolayer can magnetize Bi2Se3 surfaces via van der Waals interactions, providing a new method to realize QAHE in heterostructures.

Findings

CrI3 monolayer creates sizable spin splitting at the Dirac point.

Established rules linking quantum parameters through model analysis.

Guidelines for high-temperature QAHE in heterostructures.

Abstract

To magnetize surfaces of topological insulators without damaging their topological feature is a crucial step for the realization of the quantum anomalous Hall effect (QAHE), and still remains as a challenging task. Through density functional calculations, we found that adsorption of a two-dimensional van der Waals (2D-vdW) ferromagnetic insulator CrI3 monolayer can create a sizable spin splitting at the Dirac point of the topological surface states of Bi2Se3 films. Furthermore, general rules that connect different quantum and topological parameters are established through model analyses. This work provides a useful guideline for the realization of QAHE at high temperature in heterostructures of 2D-vdW magnetic monolayers and topological insulators.