Dependence of band structures on stacking and field in layered graphene

Novel systems of layered graphene are attracting interest for theories and applications. The stability, band structures of few-layer graphite films, and their dependence on electric field applied along the c-axis are examined within the density functional theory. We predict that those of Bernal type and also rhombohedral type tri- and tetra-layer graphite films exhibit stability. Rhombohedral-type systems, including AB-bilayer, show variable band gap induced by perpendicular electric fields, whereas the other systems, such as the Bernal-type films, stay semi-metallic. (c) 2007 Elsevier Ltd. All rights reserved.