Conductance of a photochromic molecular switch with graphene leads

TL;DR

This study uses ab initio calculations to analyze how a diarylethene molecular switch's conductance varies with different isomers and external biases when connected to graphene electrodes, highlighting the role of molecular and graphene electronic states.

Contribution

It provides a detailed, self-consistent ab initio analysis of the conductance in a graphene-molecule-graphene system, emphasizing the influence of molecular isomers and graphene edge states.

Findings

Conductance differs significantly between the two photochromic isomers.

Edge states of graphene influence the conductance properties.

Switching can be induced by applying a large potential difference.

Abstract

We report a full self-consistent ab initio calculation of the conductance of a diarylethene-based molecular switch with two graphene electrodes. Our result show the contributions of the resonant states of the molecule, of the electrode density of states, and of graphene unique features such as edge states. The conductivities are found to be significantly different for the two photochromic isomers at zero and finite applied bias. Further we point out the possibility of causing the switching by the application of a large potential difference between the two electrodes.