Raman spectroscopy at the edges of multilayer graphene

TL;DR

This study investigates the Raman spectral features at the edges of multilayer graphene, revealing insights into edge configurations and their spectral signatures, which are crucial for understanding graphene's edge-related properties.

Contribution

The paper introduces a detailed analysis of Raman spectra at graphene edges, identifying specific spectral signatures and configurations in multilayer graphene.

Findings

D band at the edge resembles that of disordered (n+1)LG

Identified two types of edge alignment configurations

Spectral features help distinguish edge structures

Abstract

Edges naturally exist in a single-layer graphene sample. Similarly, individual graphene layers in a multilayer graphene sample contribute their own edges. We study the Raman spectrum at the edge of a graphene layer laid on n layer graphene (nLG). We found that the D band observed from the edge of the top graphene layer exhibits an identical line shape to that of disordered (n+1)LG induced by ion-implantation. Based on the spectral features of the D and 2D bands, we identified two types of alignment configurations at the edges of mechanically-exfoliated bilayer and trilayer graphenes, whose edges are well-aligned from their optical images.