First-principles Calculations of the Quasiparticle and Optical Excitations in Metallic Carbon Nanostructures

ORAL

Abstract

The band structure of metallic single-walled carbon nanotubes (SWNTs) may be viewed as a cut of the graphene band structure through the Dirac point. Despite the screening due to carriers at the Fermi energy, metallic nanotubes have been predicted theoretically and confirmed experimentally to exhibit strong many-electron interaction effects in their quasiparticle and optical properties, including the existence of excitons. We have carried out a systematic study, based on the first-principles GW approach, of the quasiparticle properties of metallic nanotubes with diameters ranging from 0.5 to 1.5 nm as well as those of single-layer graphene sheets. We present results (converged with a very fine k-point grid) using both the generalized plasmon-pole (GPP) model as well as a direct treatment of dynamic screening from the RPA dielectric response. We calculate the quasiparticle band structures, lifetimes and spectral functions for both the doped and undoped cases. We present first-principles calculations of excitons and the optical response of metallic carbon nanotubes for the same range of diameters within the Bethe-Salpeter approach.

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Authors

  • Jack Deslippe

    UC Berkeley and Lawrence Berkeley National Lab

  • Cheol-Hwan Park

    UC Berkeley, Department of Physics, University of California, Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory, UC Berkeley and Lawrence Berkeley National Lab

  • Manish Jain

    University of California, Berkeley, Lawrence Berkeley National Laboratory and University of Texas, Austin, UC Berkeley and Lawrence Berkeley National Lab

  • Steven G. Louie

    UC Berkeley and Lawrence Berkeley National Laboratory, Department of Physics, University of California, Berkeley. Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California, University of California at Berkeley and Lawrence Berkeley National Lab, University of California at Berkeley and Lawrence Berkeley National Laboratory, University of California, Berkeley and Lawrence Berkeley National Laboratory, UC Berkeley, Department of Physics, University of California, Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory, UC Berkeley and Lawrence Berkeley National Lab, UC Berkeley and LBNL, Department of Physics, University of California, Berkeley, and Materials Science Division, Lawrence Berkeley National Laboratory, Dept. of Physics, University of California Berkeley and The Molecular Foundry, LBNL, Department of Physics, University of California at Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720