Simulating graphene-based single-electron transistor: incoherent current effects due to the presence of electron-electron interaction

TL;DR

This paper models a graphene-based single-electron transistor using atomistic simulations to understand how electron-electron interactions influence incoherent current effects, reproducing experimental phenomena like Coulomb blockade.

Contribution

It introduces a detailed atomistic simulation approach incorporating electron-electron interactions to analyze incoherent transport effects in graphene-based single-electron transistors.

Findings

Reproduces Coulomb blockade and Coulomb diamonds experimentally observed.

Shows incoherent effects due to electron-electron interactions significantly influence transport.

Separates contributions to electronic transport, highlighting the role of interactions.

Abstract

Carbon-based nanostructures have unparalleled electronic properties. At the same time, using an allotrope of carbon as the contacts can yield better device control and reproducibility. In this work, we simulate a single-electron transistor composed of a segment of a graphene nanoribbon coupled to carbon nanotubes electrodes. Using the non-equilibrium Green's function formalism we atomistically describe the electronic transport properties of the system including electron-electron interactions. Using this methodology we are able to recover experimentally observed phenomena, such as the Coulomb blockade, as well as the corresponding Coulomb diamonds. Furthermore, we are able to separate the different contributions to transport and show that incoherent effects due to the interaction play a crucial role in the transport properties depending on the region of the stability diagram being considered.