Decoherence of fermions subject to a quantum bath

TL;DR

This paper reviews a new technique for analyzing how quantum baths cause decoherence in many-fermion systems, especially in ballistic interferometers like the electronic Mach-Zehnder setup, highlighting key features and implications.

Contribution

It introduces a novel method for studying decoherence in many-fermion systems affected by quantum baths, extending previous single-particle analyses.

Findings

Decoherence effects in many-fermion systems are characterized using the new technique.

Application to electronic Mach-Zehnder interferometers reveals main decoherence features.

Brief discussion links these results to weak localization phenomena.

Abstract

The destruction of quantum-mechanical phase coherence by a fluctuating quantum bath has been investigated mostly for a single particle. However, for electronic transport through disordered samples and mesoscopic interference setups, we have to treat a many-fermion system subject to a quantum bath. Here, we review a novel technique for treating this situation in the case of ballistic interferometers, and discuss its application to the electronic Mach-Zehnder setup. We use the results to bring out the main features of decoherence in a many-fermion system, and briefly discuss the same ideas in the context of weak localization.