Time-reversal symmetric topological metal

TL;DR

This paper introduces a new class of topological metals protected by time-reversal symmetry, which do not require magnetic flux and exhibit unique edge states despite having a zero Chern number.

Contribution

It proposes a novel time-reversal symmetric topological metallic phase that simplifies realization and differs from traditional topological metals created from insulators.

Findings

Topological metallic phase exists with zero Chern number.

Distinct cases of metallic phases identified via edge state features.

Simplifies the experimental realization of topological metals.

Abstract

Topological metals possess gapless band structures accompanied with nontrivial edge states. Topological metals are created from the topological insulators by adjusting the magnetic flux. Here we propose the time-reversal symmetry protected topological metal without employing the magnetic flux. Topological metallic phase presents although the Chern number vanishes. In the topologically nontrivial phase, three different cases in the metallic phase are distinguished from the band-touching and in-gap features of the topological edge states. These findings shed light on the time-reversal symmetric topological metals and greatly simplify the realization of topological metals.