Decoherence and Full Counting Statistics in a Mach-Zehnder Interferometer

TL;DR

This paper studies how classical fluctuations affect charge transfer statistics in a Mach-Zehnder interferometer, revealing suppression of interference effects and new voltage-dependent cumulant behaviors.

Contribution

It provides a detailed analysis of full counting statistics under classical noise, including calculations of the first three cumulants and an approximation for high voltages.

Findings

Fluctuating potential suppresses Aharonov-Bohm oscillations in charge distribution.

Third cumulant shows a cubic voltage dependence due to fluctuations.

High voltage regime approximates the generating function effectively.

Abstract

We investigate the Full Counting Statistics of an electrical Mach-Zehnder interferometer penetrated by an Aharonov-Bohm flux, and in the presence of a classical fluctuating potential. Of interest is the suppression of the Aharonov-Bohm oscillations in the distribution function of the transmitted charge. For a Gaussian fluctuating field we calculate the first three cumulants. The fluctuating potential causes a modulation of the conductance leading in the third cumulant to a term cubic in voltage and to a contribution correlating modulation of current and noise. In the high voltage regime we present an approximation of the generating function.