Finite temperature quantum noise correlations as a probe for topological helical edge modes

TL;DR

This paper demonstrates that finite temperature quantum noise measurements can effectively distinguish between different types of helical edge modes, providing a practical tool for identifying topological phases in realistic experimental conditions.

Contribution

The study introduces a method to differentiate chiral, trivial helical, and topological helical edge modes using finite temperature quantum noise, validated at finite frequencies.

Findings

Quantum noise measurements distinguish edge mode types.

Thermal and shot noise components analyzed.

Results applicable at finite frequencies.

Abstract

The distinction between chiral, trivial helical, and topological helical edge modes can be effectively made using quantum noise measurements at finite temperatures. Quantum noise measurements consist of mainly two components. The first is thermal noise, whose provenance is thermal fluctuations, and the second is shot noise, whose origin is the quantum nature of charge particles. Studying these edge modes at finite temperatures is important as it more accurately reflects the conditions in real-world experiments. Additionally, we have verified that our results for finite temperature quantum noise correlations are valid at finite frequencies too.