First-Principles Study of the Potential Step in Metal/Graphene Contact

Metal-graphene contacts play a critical role in graphene-based electronics. The potential steps of graphene contact with eight different kinds of metals and many other electronic properties were obtained using first-principles DFT calculation. Core potential of some C atoms are used as reference to get the change of Fermi level between isolated and contacted graphene no matter whether the Dirac point could be seen in the bandstructure or not. Our results show that there are two kinds of contacts except Pd. The strong chemical contact is preferred when comes to transport.