Phonon Cerenkov amplification in graphene

ORAL

Abstract

A model of phonon Cerenkov amplification in graphene is used to explain the observed superlinear growth of resistivity for drift velocities above the speed of sound. When the electronic drift velocity exceeds the speed of sound, the phonon population is amplified by the electron-phonon coupling, with a positive amplification rate in a cone centered about the direction of the drift velocity. The resulting position-dependent nonequilibrium phonon population gives rise to a resistivity that increases exponentially along the length of the graphene sample, with a growth rate equal to the maximum phonon amplification rate divided by the speed of sound. This effect increases in magnitude linearly with both the drift velocity and the carrier density. Our theoretical calculations agree qualitatively with experimental results and pave the way for a more sophisticated model which includes self-consistently the out-of-equilibrium distributions of electrons and phonons.

–

Publication: Barajas-Aguilar, et. al. "Electrically-driven amplification of terahertz acoustic waves in graphene" arXiv:2310.12225

Presenters

  • Eric B Barrett

    • Brown University

Authors

  • Eric B Barrett

    • Brown University

  • Aaron H Barajas Aguilar

    • University of California, Irvine

  • Jasen Zion

    • Caltech

  • Ian Sequeira

    • University of California, Irvine

  • Andrew Barabas

    • University of California, Irvine

  • Takashi Taniguchi

    • Kyoto Univ
    • National Institute for Materials Science
    • Research Center for Materials Nanoarchitectonics
    • Research Center for Materials Nanoarchitectonics, National Institute for Materials Science
    • National Institute for Materials Sciences
    • NIMS
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Material Science
    • International Center for Materials Nanoarchitectonics, NIMS, Japan
    • International Center for Materials Nanoarchitectonics, Tsukuba
    • National Institue for Materials Science
    • Kyoto University
    • National Institute of Materials Science
    • International Center for Materials Nanoarchitectonics and National Institute for Materials Science

  • Kenji Watanabe

    • National Institute for Materials Science
    • NIMS
    • Research Center for Electronic and Optical Materials, National Institute for Materials Science
    • Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Material Science

  • Thomas Scaffidi

    • University of California, Irvine

  • Javier D Sanchez-Yamagishi

    • University of California, Irvine