Designing Band Structures by Patterned Dielectric Superlattices

TL;DR

This paper explores how patterned dielectric superlattices can be used to engineer the electronic band structure of graphene, demonstrating the ability to open a mass gap and create Chern bands through various pattern geometries and device parameters.

Contribution

It introduces a comprehensive modeling approach combining quantum capacitance, tight-binding, and continuum models to analyze the effects of patterned dielectric superlattices on graphene's electronic properties.

Findings

Patterned dielectric superlattices can induce a mass gap in graphene.

Emergence of Chern bands due to long-range Coulomb interactions.

Device parameters significantly influence the electronic structure.

Abstract

We investigate the electronic structure of graphene monolayers subjected to patterned dielectric superlattices. Through a quantum capacitance model approach, we simulate realistic devices capable of imposing periodic potentials on graphene. By means of both tight-binding and continuum models, we analyze the electronic structure across varied patterning geometries, including triangular, kagome, and square configurations. We explicitly explore the influence of device parameters such as the superlattice potential strength, geometry, and periodicity on the electronic properties of graphene. By introducing a long-range Coulomb interaction, we found an emergent periodic potential strong enough to open a mass gap, thereby generating a Chern band. Our study highlights the robustness and versatility of patterned dielectric superlattices for band engineering in graphene systems.