Superlattice Structures of Graphene based Nanoribbons

TL;DR

This paper predicts that superlattice structures formed by periodic junctions of graphene nanoribbons with varying widths can be engineered to modulate electronic properties and confine specific states, enabling novel nanodevice designs.

Contribution

First-principles calculations demonstrate how to create and control superlattice heterostructures of graphene nanoribbons with tunable electronic properties.

Findings

Width and energy gap modulation in superlattices

Confined electronic states in specific segments

Potential for designing novel nanodevices

Abstract

Based on first-principles calculations we predict that periodically repeated junctions of armchair graphene nanoribbons of different widths form superlattice structures. In these superlattice heterostructures the width and the energy gap are modulated in real space and specific states are confined in certain segments. Orientation of constituent nanoribbons, their width and length, the symmetry of the junction are the structural parameters to engineer electronic properties of these quantum structures. Not only the size modulation, but also composition modulation, such as periodically repeated, commensurate heterojunctions of BN and graphene honeycomb nanoribbons result in a multiple quantum well structure. We showed that these graphene based quantum structures can introduce novel concepts to design nanodevices.