Influence of leads on signatures of strongly-correlated zero-bias anomaly in double quantum dot measurements

TL;DR

This paper investigates how the presence of leads affects the signatures of a strongly-correlated zero-bias anomaly in double quantum dot systems, showing that the anomaly remains observable despite lead influence.

Contribution

It demonstrates that the zero-bias anomaly signature persists in double quantum dots even when lead effects are included, extending previous models.

Findings

Leads modify the stability diagrams of double quantum dots.

The zero-bias anomaly signature remains visible despite lead influence.

Lead effects alter but do not obscure the anomaly's signature.

Abstract

The combination of disorder and interactions is known in many systems to produce a feature in the single-particle density of states, the shape and parameter dependence of which act as signatures of the underlying electronic state. Strong Coulomb repulsion gives rise to a host of novel phenomena, among these is a unique zero-bias anomaly. While understanding of the anomaly in bulk materials remains incomplete, a version of this anomaly can be found in an ensemble of two-site systems and hence has been predicted to be observable in parallel-coupled double quantum dots. However, prior work did not include the influence of the leads. Here we show that the presence of the leads results in changes to the projected stability diagrams but that the signature of the strongly-correlated zero-bias anomaly nonetheless remains clearly visible.