Electroluminescence from Aligned (6,5) Carbon Nanotube Films: Impact Excitation of Excitons and Trions

ORAL

Abstract

Charged excitons, i.e., trions, have attracted much interest due to their nonzero charge and spin. While the trion binding energy, defined relative to the exciton energy, is on the order of a few meV to tens of meV in III-V quantum wells and transition metal dichalcogenides, that in semiconducting single-wall carbon nanotubes (SWCNTs) can be as large as 200 meV due to enhanced Coulomb interactions in one dimension, making them clearly observable even at room temperature. Here, we present electrical creation of excitons and trions in aligned films of single-chirality (6,5) SWCNTs. Highly dense SWCNT films were prepared with minimum surfactant and without polymer wrapping to provide high conductivity and enhanced electron and hole transport inside the SWCNT film. We observed that SWCNTs aligned in the direction of the current flow emit light at a lower threshold voltage than those aligned in the perpendicular direction. This increase can be explained in terms of increased conductance in the direction of alignment. Our simulations help to elaborate the nature of the electroluminescence in the aligned CNT films.

*This work was supported by the Department of Energy Basic Energy Sciences through grant no. DEFG02-06ER46308 and the Robert A. Welch Foundation through grant no. C-1509.

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Presenters

  • Ali Mojibpour

    • Electrical and Computer Engineering, Rice University
    • Department of Electrical and Computer Engineering, Rice Univ

Authors

  • Ali Mojibpour

    • Electrical and Computer Engineering, Rice University
    • Department of Electrical and Computer Engineering, Rice Univ

  • Motonori Nakamura

    • Department of Systems, Control and Information Engineering, National Institute of Technology, Asahikawa College

  • Saunab Ghosh

    • Department of Electrical and Computer Engineering, Rice Univ

  • Davoud Adinehloo

    • Electrical Engineering, State University of New York at Buffalo
    • Department of Electrical Engineering, University at Buffalo

  • Natsumi Komatsu

    • Department of Electrical and Computer Engineering, Rice Univ
    • Rice Univ

  • Weilu Gao

    • Electrical and Computer Engineering, University of Utah
    • Department of Electrical and Computer Engineering, The University of Utah

  • Yohei Yomogida

    • Department of Physics, Tokyo Metropolitan University
    • Tokyo Metropolitan University

  • Kazuhiro Yanagi

    • Department of Physics, Tokyo Metropolitan University
    • Tokyo Metropolitan University

  • Vasili Perebeinos

    • State Univ of NY - Buffalo
    • EE, State Univ of NY - Buffalo
    • Electrical Engineering, State University of New York at Buffalo
    • Department of Electrical Engineering, University at Buffalo
    • University at Buffalo
    • Department of Electrical Engineering, State Univ of NY - Buffalo

  • Junichiro Kono

    • Electrical and Computer Engineering, Rice University
    • Department of Electrical and Computer Engineering, Rice Univ
    • Rice University
    • Rice Univ
    • Department of Electrical and Computer Engineering, Rice University
    • Department of Physics and Astronomy, Rice University