Electron-phonon coupling mechanism, Kohn anomalies and Peierls instabilities in two-dimensional graphite and single-wall carbon nanotubes

ORAL

Abstract

The electron-phonon coupling in two-dimensional graphite and metallic single-wall carbon nanotubes (SWNTs) is analyzed. The $G'$-band phonon mode opens a dynamical band gap that induces a Kohn anomaly in two-dimensional graphite, while truly metallic armchair SWNTs undergo Peierls transitions driven by the $G$- and $G'$-band phonon modes. The dynamical band gap induces a non-linear dependence of the phonon frequencies on the doping level and gives rise to strong anharmonic effects.

*The MIT authors acknowledge financial support under NSF Grant DMR 04-05538. The Tohoku University authors acknowledge a Grant-in-Aid (No. 16076201) from the Ministry of Education, Japan.

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Authors

  • Georgy Samsonidze

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

  • Eduardo Barros

  • Riichiro Saito

    • Department of Physics, Tohoku University and CREST JST, Sendai, 980-8578, Japan
    • Tohoku University, CREST JST

  • Hyungbin Son

    • Department of Electrical Engineering and Computer Science
    • Massachusetts Institute of Technology
    • MIT

  • Gene Dresselhaus

    • Francis Bitter Magnet Laboratory
    • MIT
    • Massachusetts Institute of Technology

  • Mildred Dresselhaus

    • Massachusetts Institute of Technology
    • Department of Electrical Engineering and Computer Science and Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139
    • MIT