C S Ting
University of Houston, USA
Title: Novel electronic properties of hydrogenated grapheme: The first principles calculations
Biography
Biography: C S Ting
Abstract
Fully- and semi-hydrogenated graphene, named graphane (C6H6)1,2 and graphone (C6H3)3,4, were previously found to be nomagnetic semiconductor with a direct gap of 3.5 eV and antiferromagnetic semiconductor with an indirect gap of 2.46 eV, respectively. Here, by means of first-principles calculations, we predict another kinds of partially hydrogenated graphene systems5: C6H1 and C6H5, which are ferromagnetic (FM) semimetal and FM narrow-gaped semiconductor with an indirect gap of 0.7 eV respectively. When properly doped, the Fermi surface of the two systems consists of an electron pocket or six hole patches in the first Brillouin zone with completely spin-polarized charge carries. If superconductivity exists in these systems, the stable pairing-symmetries are shown to be p + ip for electron doped case, and anisotropic p + ip for hole doped case. The predicted systems may provide fascinating platforms for studying the novel properties of ferromagnetism and triplet-pairing superconductivity. In addition, the electronic structures of hydrogenated graphene C6H2 and C6H4 have also been studied. We find that C6H2 is a Dirac semimetal with 2 highly anisotropic cones located well inside the first Brillouin zone, and C6H4 is a semiconductor with a gap of ~3.35 eV. A detailed discussion of their properties will be presented.