Edge states of moir\'e structures in graphite

TL;DR

This paper investigates the origin of bead-like edge states in moiré patterns of graphite, revealing they are centered around AB stacking sites, contrary to previous assumptions, supported by STM measurements and tight-binding calculations.

Contribution

It provides new insights into the spatial localization of edge states in moiré structures, challenging the common assumption of their association with AA sites.

Findings

Edge states are centered around AB stacking sites.

STM measurements show bead intensity shifts with moiré pattern.

Tight-binding calculations corroborate experimental observations.

Abstract

We address the origin of bead-like edge states observed by scanning tunneling microscopy (STM) in moir\'e patterns of graphite. Low-bias scanning tunneling spectroscopy measurements indicate these edge states are centered around AB stacking sites, contrarily to the common assumption of them being at AA sites. This shift of the intensity of the beads with respect to the bulk moir\'e pattern has been corroborated by a tight-binding calculation of the edge states in bilayer nanoribbons. Our results are valid not only for graphite but also for few-layer graphene, where these states have also been recently observed.