Theoretical Study Of Electronic Property In Graphene Under Regulation Of Tensile Force

Graphene is a single layer of layered graphite. Since graphene was prepared successfully in experiment by Geim's research group from Manchester University in 2004, this single carbon atomic two-dimensional sheet has attracted a great deal of attention. Graphene not only is the thinnest material in the world, but also has a number of very peculiar electronic properties which make it a promising candidate for future electronic applications.In this paper, for model of graphene ribbons with zigzag shaped edges and armchair shaped edges drawn vertically by the tensile force. The relations between a tensile force and deformation of graphene, hybrid orbital component of carbon atom are investigated using static mechanics and the hybridization theory of orbital. According to this model and relations, we also investigate the relations between the tensile force and energy bands, energy gaps of graphene based on considering the only nearest-neighbor and three neighbors though the tight-binding method.In the study of the relations between a tensile force and deformation of graphene, hybrid orbital component, we obtain the analytic relations between a tensile force andbond angle, bond length, s -orbital and p -orbital components. We also find thoughnumerical calculation: for zigzag shaped edges, the s -orbital components of two hybrid orbitals symmetrical to the tensile force decrease with the force and onecoaxial to the force increases with. The case of p_x -orbital components is just opposite to that of s -orbital components and p_y,-and p_z -orbital components areunchanged. For armchair shaped edges, the results are opposite to that of zigzag edges. In the study of the relations between the tensile force and energy bands, energy gaps of graphene, for considering the only nearest-neighbor and three neighbors, we both obtain the analytic relations between the tensile force and energy bands, energy gaps of graphene in the model of graphene ribbons with zigzag shaped edges and armchair shaped edges. Though numerical calculation, we find: the energy gaps broaden as the tensile force increases besides the tensile force can make graphene open an energy gap, moreover the energy gap of graphene ribbon with zigzag shaped edges broadens more easily.