Observation of current whirlpools in graphene at room temperature

ORAL

Abstract

Classical hydrodynamics, where interparticle collisions dominate transport, can give rise to peculiar flow patterns. An analogous flow regime can also manifest itself in solid-state systems, most notably in graphene. In this talk, we present an experiment where we imaged one of the most striking hydrodynamic transport patterns - stationary current whirlpools - in a room-temperature monolayer graphene device. Our experiment takes advantage of a scanning nitrogen-vacancy magnetometer, which is able to non-perturbatively image the current density with nanoscale resolution. We show that the appearance of vortices depends both on the characteristic device size and the carrier doping (electrons, holes) of graphene. Our demonstration opens exciting opportunities for investigating mesoscopic transport phenomena with local imaging techniques.

*This work was supported by the European Research Council through ERC CoG 817720 (IMAGINE), the Swiss National Science Foundation (SNSF) through the National Centre of Competence in Research in Quantum Science and Technology (NCCR QSIT), Grant No. 51NF40-185902, and the Advancing Science and TEchnology thRough dIamond Quantum Sensing (ASTERIQS) program, Grant No. 820394, of the European Commission. K.W. and T.T. acknowledge support from the JSPS KAKENHI (Grant Numbers 20H00354, 21H05233 and 23H02052) and World Premier International Research Center Initiative (WPI), MEXT, Japan.

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Publication: Palm, Marius L., Ding, Chaoxin, Huxter, William S., Taniguchi Takashi, Watanabe Kenji, Degen, Christian L. "Observation of Current Whirlpools in Graphene at Room Temperature." Under review (2023)

Presenters

  • Chaoxin Ding

    • ETH Zurich

Authors

  • Chaoxin Ding

    • ETH Zurich

  • Marius L Palm

    • ETH Zurich

  • William S Huxter

    • ETH Zurich

  • 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

  • Christian L Degen

    • ETH Zurich