Restoration of topological properties at finite temperatures in a heavy-fermion system

TL;DR

This paper investigates how topological phases in a heavy-fermion system evolve with temperature, revealing that thermal effects can restore topological properties such as edge modes and spin-Hall conductivity.

Contribution

It introduces a finite-temperature phase diagram for a topological heavy-fermion system and uncovers temperature-induced restoration of topological features.

Findings

Topological properties are restored at finite temperatures.

Spin-Hall conductivity increases with temperature.

Gapless edge modes emerge as temperature rises.

Abstract

We study how topological phases evolve in the Kane-Mele-Kondo lattice at finite temperatures and obtain the topological Doniach phase diagram. In particular, we find an intriguing crossover behavior induced by the interplay between the topological structure and electron correlations; the topological properties are restored by temperature effects. This restoration can be observed in the behavior of the bulk as well as the edge. In the bulk, we observe an increase of the spin-Hall conductivity at finite temperatures, while it is zero in the low temperature region. At the edge, we observe gapless edge modes emerging with increasing temperature.