Tight Binding Descriptions of Graphene and Its Derivatives

Abstract

Graphene is an effectively two dimensional form of carbon atoms arranged in honeycomb lattice. Due to its lightweight, high electron mobility and other special electronic properties it is considered both an academically interesting and industrially promising candidate for various electronics applications. Many investigations focused on graphene require theoretical simulations to be performed over a large number of unit cells of graphene. For simulation scenarios where ab-initio methods are computationally too costly, researchers often refer to the low-cost but still highly accurate tight-binding (TB) model. In TB model, the electron interaction is parametrized, either through the derivation of parameters using first principles methods, or by fitting to experimental results. The results of TB simulations depend strongly on this parameterization, therefore it is very important to know the level of accuracy and transferability of these parameters. In this research project we will simulate the band structure and density of states of graphene and other derivative of carbon structures such as nanoribbons using a state-of-the-art parameter set; and compare their performance to the results of ab initio calculations. The resulting comparison will serve as a benchmark for future studies on graphene and derivatives.