Spin-Orbit Coupling in Transition Metal Dichalcogenide Heterobilayer Flat Bands

TL;DR

This paper models the spin-orbit coupling effects in TMD heterobilayers, revealing topological phases and providing a basis for understanding interactions and experimental phenomena in these materials.

Contribution

It introduces a tight-binding model incorporating spin-dependent hoppings that captures the topological properties of TMD heterobilayer flat bands.

Findings

Strong intralayer spin-orbit coupling in flat bands

Electric field induces interlayer hybridization akin to the Kane-Mele model

Model serves as a foundation for exploring topological phases

Abstract

The valence flat bands in transition metal dichalcogenide (TMD) heterobilayers are shown to exhibit strong intralayer spin-orbit coupling. This is reflected in a simple tight-binding model with spin-dependent complex hoppings based on the continuum model. A perpendicular electric field causes interlayer hybridization, such that the effective model is equivalent to the Kane-Mele model of topological insulators. The proposed model can be used as a starting point to understand interactions and the experimentally observed topological phases.