Electron-electron interactions in decoupled graphene layers

TL;DR

This paper investigates how inter-layer interactions in multi-layer graphene on silicon carbide influence Fermi liquid properties, revealing increased correlation energies and decreased quasiparticle velocities despite weak inter-layer coherence.

Contribution

It demonstrates that inter-layer interactions significantly affect electronic properties even with negligible inter-layer coherence in decoupled graphene layers.

Findings

Inter-layer interactions increase correlation energies.

They decrease quasiparticle velocities.

They reduce the influence of exchange and correlation on carrier distribution.

Abstract

Multi-layer graphene on the carbon face of silicon carbide is an intriguing electronic system which typically consists of a stack of ten or more layers. Rotational stacking faults in this system dramatically reduce inter-layer coherence. In this article we report on the influence of inter-layer interactions, which remain strong even when coherence is negligible, on the Fermi liquid properties of charged graphene layers. We find that inter-layer interactions increase the magnitudes of correlation energies and decrease quasiparticle velocities, even when remote-layer carrier densities are small, and that they lessen the influence of exchange and correlation on the distribution of carriers across layers.