Electronic properties of graphene and boron-nitride based nanostructured materials

Abstract

We study the electronic properties of graphene with periodic structural modifications using the local density approximation within the framework of the density functional theory. It is found that the double-layer graphene with nanotube arrays which connect the two sheets seamlessly is a direct-gap semiconductor. Also the single-layer graphene with periodic holes of 24-atomic-site vacancy is found to have a sizable direct fundamental gap as well. These graphene-based materials should be of high importance for nanoelectronics applications in the future. In addition, we study the electronic structure of the superlattice composed of graphene and boron-nitride layers which are stacked alternately. The material is found to be metallic even though each graphene layer is sandwiched by insulating BN layers and is very far from other graphene layers. The material may show interesting electronic properties being different from those of graphene.