Spin-textured Chern bands in AB-stacked transition metal dichalcogenide bilayers

TL;DR

This paper demonstrates the emergence of topological moire bands with spin textures in AB-stacked TMD bilayers, revealing a tunable platform for quantum spin Hall and quantum anomalous Hall effects through first principles and continuum modeling.

Contribution

It introduces a method to create topological bands in AB-stacked TMD bilayers, combining first principles calculations with continuum modeling to reveal valley contrasting Chern bands.

Findings

Displacement field induces topological moire bands in AB-stacked TMD heterobilayers.

Valley contrasting Chern bands with non-trivial spin textures are formed.

The study provides a recipe for realizing quantum spin Hall and quantum anomalous Hall effects.

Abstract

While transition metal dichalcogenide (TMD) based moire materials have been shown to host various correlated electronic phenomena, topological states have not been experimentally observed until now. In this work, using first principles calculations and continuum modeling, we reveal the displacement field induced topological moire bands in AB-stacked TMD heterobilayer MoTe2/WSe2. Valley contrasting Chern bands with non-trivial spin texture are formed from interlayer hybridization between MoTe2 and WSe2 bands of nominally opposite spins. Our study establishes a recipe for creating topological bands in AB stacked TMD bilayers in general, which provides a highly tunable platform for realizing quantum spin Hall and interaction induced quantum anomalous Hall effects.