Single-slit electron diffraction analog in a graphene based device

ORAL

Abstract

Graphene’s unique properties steming from its ability to host massless Dirac fermions, continue to make it a vital material for various applications. This raises questions about measuring wavelike behavior, particularly in the context of Dirac fermions. These devices, when coupled with improved fabrication techniques, offer a foundation for diffraction based switch mechanisms. This talk presents an observation of single slit diffraction by massless Dirac fermions in graphene, fully encapsulated with hexagonal boron nitride on a back-gated SiO2 substrate. These massless Dirac fermions exhibit an effective de Broglie wavelength corresponding to their Fermi energy and applied gate voltage. Nanometer-scale device designs were implemented to fabricate a single-slit followed by five detector paths. Predictive calculations were employed to interpret the observations by modelling the ideal wave propagation scenarios within the designed devices to provide an accurate description of the observed phenomenon. The experiments were conducted both at room temperature and at 190 K. The colder temperature revealed an exaggerated asymmetry in the electrical properties of electrons and holes, with differing Fermi velocities near the K point considered as a potential contributing factor. This observation of single-slit diffraction and the associated device concept hold promise for the development of diffraction switches with versatile applications in various fields.

*D.W. was supported by an appointment to the Intelligence Community Postdoctoral Research Fellowship Program at the University of Washington (UW) administered by the Oak Ridge Institute for Science and Education through an interagency agreement between the U.S. Department of Energy and the Office of the Director of National Intelligence. Device fabrication at UW was supported by the National Science Foundation CAREER Award No. DMR-2041972. Work presented herein was performed, for a subset of the authors, as part of their official duties for the U.S. Government. Funding is hence appropriated by the U.S. Congress directly.

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Publication: Saha, D., Waters, D., Yeh, C.-C., Mhatre, S.M., et al. (2023). "Graphene-based analog of single-slit electron diffraction." Physical Review B 108(12): 125420.

Presenters

  • Swapnil M Mhatre

    • Theiss Research

Authors

  • Swapnil M Mhatre

    • Theiss Research

  • Dipanjan Saha

    • Northrop Grumman

  • Dacen Waters

    • University of Washington

  • Ching-Chen Yeh

    • National Taiwan University

  • Ngoc Thanh Mai Tran

    • National Institute of Standards and Technology
    • Physical Measurement Laboratory, National Institute of Standards & Technology, Gaithersburg, Maryland. & Joint Quantum Institute, University of Maryland, College Park, MD
    • Physical Measurement Laboratory, NIST

  • Heather M Hill

    • National Institute of Standards and Technology

  • 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

  • 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

  • David B Newell

    • National Institute of Standards and Technology

  • Matthew Yankowitz

    • University of Washington

  • Albert F Rigosi

    • Physical Measurement Laboratory, National Institute of Standards & Technology
    • National Institute of Standards and Technology