Correlated electron tunneling through two separate quantum dot systems with strong capacitive interdot coupling

TL;DR

This paper investigates how correlated electron tunneling can overcome Coulomb blockade in a double quantum dot system with strong capacitive coupling, revealing Kondo correlations through experiments and numerical calculations.

Contribution

It demonstrates the emergence of Kondo correlations in strongly interacting double quantum dots and compares experimental results with numerical renormalization group calculations.

Findings

Correlated tunneling overcomes Coulomb blockade at increased tunnel coupling.

Experimental results align with numerical renormalization group predictions.

Evidence of Kondo correlations due to electrostatic interaction in the system.

Abstract

A system consisting of two independently contacted quantum dots with strong electrostatic interaction shows interdot Coulomb blockade when the dots are weakly tunnel coupled to their leads. It is studied experimentally how the blockade can be overcome by correlated tunneling when tunnel coupling to the leads increases. The experimental results are compared with numerical renormalization group calculations using predefined (measured) parameters. Our results indicate Kondo correlations due to the electrostatic interaction in this double quantum dot system.