Tuning edge state localization in graphene nanoribbons by in-plane bending

TL;DR

This paper investigates how in-plane bending affects the electronic edge states in graphene nanoribbons, revealing that increased bending causes gradual delocalization of these states, with implications for strain-engineered electronic properties.

Contribution

It introduces a computationally efficient tight-binding model to analyze the impact of in-plane bending on edge state localization in graphene nanoribbons.

Findings

Edge states are sensitive to bending and develop an effective dispersion.

Increased bending leads to gradual delocalization of edge states.

The model accurately describes the electronic structure with low computational cost.

Abstract

The electronic properties of graphene are influenced by both geometric confinement and strain. We study the electronic structure of in-plane bent graphene nanoribbons, systems where confinement and strain are combined. To understand its electronic properties, we develop a tight-binding model that has a small computational cost and is based on exponentially decaying hopping and overlap parameters. Using this model, we show that the edge states in zigzag graphene nanoribbons are sensitive to bending and develop an effective dispersion that can be described by a one-dimensional atomic chain model. Because the velocity of the electrons at the edge is proportional to the slope of the dispersion, the edge states become gradually delocalized upon increasing the strength of bending.