The Electronic Structure of Few-Layer Graphene: Probing the Evolution from a 2-Dimensional to a 3-Dimensional Material

TL;DR

This study investigates how the electronic structure of few-layer graphene evolves from a two-dimensional to a three-dimensional form by measuring optical conductivity spectra across different layer counts, revealing a unified scaling behavior.

Contribution

It provides a comprehensive characterization of the electronic structure evolution in few-layer graphene using optical measurements and a zone-folding model, connecting monolayer to bulk graphite.

Findings

Distinct infrared peaks scale with layer number

Electronic structure can be derived from bulk graphite

Unified zone-folding scheme explains observations

Abstract

While preserving many of the unusual features of single-layer graphene, few-layer graphene (FLG) provides a richness and flexibility of electronic structure that render this set of materials of great interest for both fundamental studies and applications. Essential for progress, however, is an understanding of the evolution of the electronic structure of these materials with increasing layer number. In this report, the evolution of the electronic structure of FLG, for N = 1 - 8 atomic layers, has been characterized by measurements of the optical conductivity spectra. For each layer thickness N, distinctive peaks are found in the infrared range, with positions obeying a simple scaling relation. The observations are explained by a unified zone-folding scheme that generates the electronic structure for all FLG materials from that of bulk graphite.