Stability of edge states and edge magnetism in graphene nanoribbons

TL;DR

This paper critically examines the stability of edge states and magnetism in graphene nanoribbons, highlighting mechanisms that can suppress or eliminate magnetic edge states and their instability at room temperature.

Contribution

It identifies key mechanisms like edge reconstruction, passivation, and closure that reduce or eliminate edge states and magnetism in graphene nanoribbons.

Findings

Edge states may not exist in real systems due to natural mechanisms.

Intrinsic magnetism in ZGNRs is unstable at room temperature.

Charge doping and edge defects further destabilize edge magnetism.

Abstract

We critically discuss the stability of edge states and edge magnetism in zigzag edge graphene nanoribbons (ZGNRs). We point out that magnetic edge states might not exist in real systems, and show that there are at least three very natural mechanisms - edge reconstruction, edge passivation, and edge closure - which dramatically reduce the effect of edge states in ZGNRs or even totally eliminate them. Even if systems with magnetic edge states could be made, the intrinsic magnetism would not be stable at room temperature. Charge doping and the presence of edge defects further destabilize the intrinsic magnetism of such systems.