Energy gap tuning in graphene on hexagonal boron nitride bilayer system

TL;DR

This paper investigates how an electric field can tune the energy gap in graphene on hexagonal boron nitride bilayers, enabling control over electronic properties for nanoelectronics.

Contribution

It demonstrates the effect of perpendicular electric fields on the band structure and energy gap of graphene/hBN bilayers using theoretical methods.

Findings

Electric field significantly modifies the band structure.

Energy gap can be controlled via electric field.

Carrier mobility may surpass that in bilayer graphene.

Abstract

We use a tight binding approach and density functional theory calculations to study the band structure of graphene/hexagonal boron nitride bilayer system in the most stable configuration. We show that an electric field applied in the direction perpendicular to the layers significantly modifies the electronic structure of the whole system, including shifts, anticrossing and other deformations of bands, which can allow to control the value of the energy gap. It is shown that band structure of biased system may be tailored for specific requirements of nanoelectronics applications. The carriers' mobilities are expected to be higher than in the bilayer graphene devices.