Periodically rippled graphene: growth and spatially resolved electronic structure

TL;DR

This study investigates the growth and electronic structure of rippled epitaxial graphene on Ru(0001), revealing periodic ripples and localized electronic inhomogeneities confirmed by experimental measurements.

Contribution

It provides a detailed analysis of the growth process and spatially resolved electronic properties of rippled graphene on Ru(0001), combining theoretical modeling with experimental validation.

Findings

Graphene forms a uniform monolayer with periodic ripples.

Electronic inhomogeneities are observed at different ripple heights.

Electron pockets are localized at the higher parts of the ripples.

Abstract

We studied the growth of an epitaxial graphene monolayer on Ru(0001). The graphene monolayer covers uniformly the Ru substrate over lateral distances larger than several microns reproducing the structural defects of the Ru substrate. The graphene is rippled with a periodicity dictated by the difference in lattice parameter between C and Ru. The theoretical model predict inhomogeneities in the electronic structure. This is confirmed by measurements in real space by means of scanning tunnelling spectroscopy. We observe electron pockets at the higher parts of the ripples.