Effect of Coulomb interaction on current noise in open quantum dots

TL;DR

This paper investigates how Coulomb interactions influence current noise in open quantum dots, revealing that interactions modify noise power even when conductance remains unaffected, due to nonequilibrium Coulomb fields.

Contribution

It demonstrates that Coulomb interactions cause corrections to current noise in open quantum dots, independent of conductance corrections, through nonequilibrium Coulomb field effects.

Findings

Interaction correction to noise power identified

Dependence of noise on temperature, voltage, and Coulomb strength established

Correction persists even with reflectionless contacts

Abstract

We analyze the effect of Coulomb interaction on the noise of electric current through an open quantum dot. We demonstrate that the ensemble average value of the noise power acquires an interaction correction even for a dot coupled to the leads by reflectionless point contacts, when the ensemble average conductance is known to have no interaction corrections. To leading order, the correction to the noise originates from the formation of a nonequilibrium state of the Coulomb field describing the interaction between electrons. We find the dependence of the current noise power on the electron temperature, the applied voltage bias, and the strength of the Coulomb interaction.