Edge State Engineering of Graphene Nanoribbons

Abstract

Zigzag edges of graphene\nnanoribbons, which are predicted to host\nspin-polarized electronic states, hold great promise for future spintronic\ndevice applications. The ability to precisely engineer the zigzag\nedge state is of crucial importance for realizing its full potential\nfunctionalities in nanotechnology. By combining scanning tunneling\nmicroscopy and atomic force microscopy, we demonstrate the zigzag\nedge states have energy splitting upon fusing manganese the phthalocyanine\nmolecule with the short armchair graphene nanoribbon termini. Moreover,\nthe edge state splitting can be reversibly switched by adsorption\nand desorption of a hydrogen atom on the magnetic core of manganese\nphthalocyanine. These observations can be explained by tuning the\nzigzag edge local doping through the charge transfer process, which\nprovides a new route to functionalize graphene-based molecular devices.