Potential Energy Landscape for hot electrons in periodically nanostructured graphene

TL;DR

This study investigates the unoccupied electronic states of periodically nanostructured graphene on Ru(0001), revealing unique energy splitting, deviations from work function modulation, and a new interfacial state, indicating quantum dot-like behavior.

Contribution

It provides new insights into the electronic structure of nanostructured graphene, highlighting unexpected features and the self-organized quantum dot behavior.

Findings

First graphene image state is energy-split.

The split state does not follow local work function.

A new interfacial state appears at +3 eV.

Abstract

We explore the spatial variations of the unoccupied electronic states of graphene epitaxially grown on Ru(0001) and observed three unexpected features: the first graphene image state is split in energy, unlike all other image states, the split state does not follow the local work function modulation, and a new interfacial state at +3 eV appears on some areas of the surface. These results show the system behaves as a self-organized periodic array of quantum dots.