Magnetized topological insulator multilayers

Abstract

Topological insulators have Dirac cone surface states protected by time-reversal symmetry (TRS). Weak magnetic order in topological insulator thin films can lead to the quantum anomalous Hall effect (QAHE), which was first realized by magnetic doping of topological insulators to establish a fragile ferromagnetic state. Recent work has established MnBi 2 Te 4 as a structurally ordered magnetic topological insulator. We report on a theoretical study of superlattices formed from M n B i 2 T e 4 and Bi 2 Te 3 building blocks that employs a simplified model validated by ab initio density-functional theory. We use it to shed light on the dependence of the quantum anomalous Hall effect on film thickness, magnetic configuration, the stacking sequences of the van der Waals coupled building blocks, and bulk electronic structure.

Document Details

Document Type
Pub Defense Publication
Publication Date
Oct 19, 2020
Source ID
10.1073/pnas.2014004117

Entities

People

  • Allan H. MacDonald
  • Chao Lei
  • Shu Chen

Organizations

  • Army Research Office
  • Robert A. Welch Foundation
  • Shanghai University
  • University of Texas at Austin

Tags

Fields of Study

  • Physics

Readers

  • Nanocomposite Materials Science
  • Quantum Chemistry
  • Quantum spin resonance or Electron Paramagnetic Resonance spectroscopy.

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene
  • Quantum Computing