Feedback effects on the current correlations in Y-shaped conductors

TL;DR

This paper investigates how voltage fluctuations in a Y-shaped conductor with external impedances influence current correlations, revealing that charge transfer moments are affected and cross-correlations can switch signs.

Contribution

It demonstrates the impact of circuit-induced voltage fluctuations on current correlations and charge transfer moments in Y-shaped conductors, a novel insight in mesoscopic transport.

Findings

Second moments are not simple rescalings of bare values due to voltage fluctuations.

Cross-correlation between outputs can change from negative to positive.

Circuit impedance influences current fluctuation behavior.

Abstract

We study current fluctuations in a Y-shaped conductor connected to external leads with finite impedances. We show that, due to voltage fluctuations in the circuit, the moments of the transferred charges cannot be obtained from simple rescaling of the bare values already in the second moments. The cross-correlation between the output terminals can change from negative to positive under certain parameter regimes.