High Chern number phase in topological insulator multilayer structures: a Dirac cone model study

TL;DR

This paper investigates high Chern number phases in topological insulator multilayer structures using a Dirac cone model, revealing how band inversion and spin polarization contribute to these phases.

Contribution

It introduces a Dirac cone model analysis to identify high Chern number phases in TI multilayers and explores additional structures and superlattices.

Findings

High Chern numbers are linked to band inversion of Dirac cones.

Spin polarization at the bGammab point increases with high Chern numbers.

Phase diagrams show the evolution of topological phases with parameters.

Abstract

We use the Dirac cone model to explore the high Chern number (C) phases that are realized in the magnetic-doped topological insulator (TI) multilayer structures by Zhao et al. [Nature 588, 419 (2020)]. The Chern number is calculated by capturing the evolution of the phase boundaries with the parameters and then the Chern number phase diagrams of the TI multilayer structures are obtained. The high-C behavior is attributed to the band inversion of the renormalized Dirac cones, along with which the spin polarization at the \Gamma point will get increased. Moreover, another two TI multilayer structures as well as the TI superlattice structures are also studied.