Distributions of electron waiting times in quantum-coherent conductors

TL;DR

This paper analyzes electron waiting time distributions in quantum-coherent conductors, extending previous models to multi-channel setups and finite temperatures, and demonstrates their use in characterizing mesoscopic scatterers.

Contribution

It generalizes electron waiting time distribution analysis to multi-channel and finite-temperature systems, providing new tools for quantum transport characterization.

Findings

Waiting time distributions reveal the number of resonant levels in interferometers.

Extended models to multi-channel conductors with temperature effects.

Applied to quantum point contacts and interferometers for detailed analysis.

Abstract

The distribution of electron waiting times is useful to characterize quantum transport in mesoscopic structures. Here we consider a generic quantum-coherent conductor consisting of a mesoscopic scatterer in a two-terminal setup. We extend earlier results for single-channel conductors to setups with several (possibly spin-degenerate) conduction channels and we discuss the effect of a finite electronic temperature. We present detailed investigations of the electron waiting times in a quantum point contact as well as in two mesoscopic interferometers with energy-dependent transmissions: a Fabry-P\'erot interferometer and a Mach-Zehnder interferometer. We show that the waiting time distributions allow us to determine characteristic features of the scatterers, for instance the number of resonant levels in the Fabry-P\'erot interferometer that contribute to the electronic transport.