Massless Fermions in multilayer graphitic systems with misoriented layers

TL;DR

This paper shows that misoriented multilayer graphene systems can exhibit massless Fermion behavior similar to single-layer graphene, affecting experimental signatures like Raman spectra and STM images.

Contribution

It demonstrates through ab initio calculations that incommensurate multilayer graphene retains massless Fermion properties and explores their experimental implications.

Findings

Massless Fermion behavior persists in misoriented multilayer graphene.

STM images are sensitive to layer arrangement.

Raman signals depend more on layer orientation than number.

Abstract

We examine how the misorientation of a few stacked graphene layers affects the electronic structure of carbon nanosystems. We present {\it ab initio} calculations on bi- and trilayer systems to demonstrate that the massless Fermion behavior typical of single layered graphene is also found in incommensurate multilayered graphitic systems. We also investigate the consequences of this property on experimental fingerprints, such as Raman spectroscopy and scanning tunneling microscopy (STM). Our simulations reveal that STM images of turbostratic few layer graphite are sensitive to the layer arrangement. We also predict that resonant raman signal of graphitic samples are more sensitive to the orientation of the layers than to their number.