The connection between noise and quantum correlations in a double quantum dot

TL;DR

This paper explores how Coulomb interactions in a double quantum dot influence electron entanglement and transport noise, revealing that shot noise measurements can directly quantify the entanglement degree.

Contribution

It demonstrates that the Fano factor of shot noise can directly measure the entanglement parameter in a double quantum dot system.

Findings

Strong Coulomb interactions induce entangled two-electron states.

The Fano factor reveals the degree of entanglement.

Transport noise signatures correlate with interaction strength.

Abstract

We investigate the current and noise characteristics of a double quantum dot system. The strong correlations induced by the Coulomb interaction create entangled two-electron states and lead to signatures in the transport properties. We show that the interaction parameter phi, which measures the admixture of the double-occupancy contribution to the singlet state and thus the degree of entanglement, can be directly accessed through the Fano factor of super-Poissonian shot noise.