Band Gaps and Quasiparticle Energies of Graphene Nanoribbons

ORAL

Abstract

We present calculations of the quasiparticle energies and band gaps of graphene nanoribbons (GNRs) carried out using a first-principles many-electron Green's function approach. The self-energy of electrons is evaluated within the GW approximation. In our supercell calculation, due to the geometry of GNRs, a rectangular truncation of the Coulomb interaction is applied, which significantly improves the efficiency of the calculation. The quasiparticle results are compared and contrasted with results from previous studies that have been carried out either within the tight-binding or density functional formalism.

*Acknowledgement: This work is supported by NSF Grant No. DMR04-39768 and by the Director, Office of Science, Office of Basic Energy under contract No. DE-AC02-05CH11231. Computational resources have been provided by DATASTAR at SDSC.

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Authors

  • Li Yang

    • Department of Physics, University of California at Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720

  • Cheol Hwan Park

    • Department of Physics, University of California at Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720

  • Young-Woo Son

    • Korea Institute for Advanced Study, Dept of Physics UC Berkeley, Mat Sci Div LBNL
    • School of Computational Sciences, Korea Institute for Advanced Study, Seoul 130-722, Korea

  • Marvin Cohen

    • Dept of Physics UC Berkeley, Mat Sci Div LBNL
    • Department of Physics, University of California at Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
    • UC Berkeley, Lawrence Berkeley National Laboratory
    • University of California at Berkeley and Lawrence Berkeley National Laboratory
    • UC Berkeley \& LBNL
    • UC Berkeley and Lawrence Berkeley National Laboratory

  • Steven Louie

    • Molecular Foundry, Lawrence Berkeley National Laboratory and Department of Physics, University of California at Berkeley
    • Dept of Physics UC Berkeley, The Molecular Foundry LBNL, Mat Sci Div LBNL
    • Department of Physics, University of California at Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
    • UC Berkeley, Lawrence Berkeley National Laboratory
    • University of California at Berkeley and Lawrence Berkeley National Laboratory
    • University of California at Berkeley
    • University of California, Berkeley \& Lawrence Berkeley National Laboratory
    • University of California at Berkeley and Lawrence Berkeley National Lab
    • Department of Physics, University of California, Berkeley, and Materials Sciences Division, Lawrence Berkeley National Laboratory