Full Current Statistics in the Regime of Weak Coulomb Interaction

TL;DR

This paper investigates how strong coupling in a Coulomb island affects current statistics, revealing that Coulomb interactions can be incorporated through renormalized transmission eigenvalues, leading to an exponentially suppressed Coulomb blockade gap.

Contribution

It introduces a method to include Coulomb interaction effects via renormalized transmission eigenvalues in strongly coupled Coulomb islands.

Findings

Coulomb interaction effects can be incorporated into transmission eigenvalues.

The Coulomb blockade gap is exponentially suppressed compared to classical charging energy.

Strong coupling weakens Coulomb interaction effects.

Abstract

We evaluate the full statistics of the current via a Coulomb island that is strongly coupled to the leads. This strong coupling weakens Coulomb interaction. We show that in this case the effects of the interaction can be incorporated into the renormalization of transmission eigenvalues of the scatterers that connect the island and the leads. We evaluate the Coulomb blockade gap in the current-voltage characteristics, the value of the gap being exponentially suppressed as compared to the classical charging energy of the island.