Topologically protected one-dimensional electronic states in group IV two-dimensional Dirac materials

TL;DR

This paper explores topologically protected one-dimensional electronic states in group IV 2D materials, highlighting their potential for quantum spin Hall effects and the impact of spin-orbit coupling and electric fields.

Contribution

It provides a comprehensive overview of topologically protected states in group IV 2D materials and introduces electric-field induced topological networks in twisted bilayer graphene.

Findings

Group IV 2D materials can host quantum spin Hall states.

Spin-orbit coupling influences electronic band structures.

Electric fields can induce topological state networks in twisted bilayer graphene.

Abstract

In this report we give a brief introduction on the occurrence of topologically protected one-dimensional electronic states in group IV two-dimensional graphene-like materials. We discuss the effect of spin-orbit coupling on the electronic band structure and show that these materials are potential candidates to exhibit the quantum spin Hall effect. The quantum spin Hall effect is characterized by a gapped interior and metallic counter-propagating spin-polarized topologically protected edges states. We also elaborate on the electric-field induced formation of a hexagonal network of one-dimensional topologically protected electronic states in small-angle twisted bilayer graphene.