Counting statistics for mesoscopic conductors with internal degrees of freedom

TL;DR

This paper analyzes electron transport in mesoscopic devices with internal quantum states, using full counting statistics to distinguish between coherent and incoherent dynamics and to identify conditions for super-Poissonian noise.

Contribution

It introduces a framework to differentiate internal quantum coherence effects from incoherent processes in mesoscopic conductors using full counting statistics.

Findings

Conditions for distinguishing coherent vs. incoherent internal dynamics

Identification of regimes producing super-Poissonian noise

Analysis of how internal degrees of freedom influence current fluctuations

Abstract

We consider the transport of electrons passing through a mesoscopic device possessing internal dynamical quantum degrees of freedom. The mutual interaction between the system and the conduction electrons contributes to the current fluctuations, which we describe in terms of full counting statistics. We identify conditions where this discriminates coherent from incoherent internal dynamics, and also identify and illustrate conditions under which the device acts to dynamically bunch transmitted or reflected electrons, thereby generating super-Poissonian noise.