Observation of plasmon-phonons in a metamaterial superconductor using inelastic neutron scattering

ORAL

Abstract

Recent experiments have demonstrated that the metamaterial approach is capable of drastically increasing the critical temperature, Tc, of composite metal-dielectric epsilon near zero (ENZ) metamaterial superconductors. For example, a tripling of the critical temperature was observed in bulk Al-Al2O3 ENZ core-shell metamaterials. A theoretical model based on the Maxwell-Garnett effective medium approximation provides a microscopic explanation of this effect in terms of electron-electron pairing mediated by a hybrid plasmon-phonon excitation in the composite metal-dielectric metamaterial. We report the first observation of a hybrid plasmon-phonon excitation in Al-Al2O3 ENZ core-shell metamaterials using inelastic neutron scattering. These results provide strong support for this novel mechanism of superconductivity in ENZ metamaterials and provide an explanation for the 50 year old mystery of enhanced Tc in granular aluminum thin films.

*This work was supported in part by DARPA W911NF1710348 and ONR N00014-18-1-2681 grants.

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Presenters

  • Vera Smolyaninova

    • Physics, Towson University
    • Towson University
    • Department of Physics Astronomy and Geosciences, Towson University

Authors

  • Vera Smolyaninova

    • Physics, Towson University
    • Towson University
    • Department of Physics Astronomy and Geosciences, Towson University

  • Jeffrey W Lynn

    • National Institute of Standards and Technology
    • NIST
    • NIST Center for Neutron Research, National Institute of Standards and Technology
    • NIST Center for neutron research, National Institute of Standard and Technology, Gaithersburg, MD

  • Nicholas Butch

    • NIST Center for Neutron Research
    • Center for Neutron Research, National Institute of Standards and Technology
    • NIST
    • NIST Center for Neutron Research, National Institute of Standards and Technology
    • National Institute of Standards and Technology
    • University of Maryland, College Park & NIST

  • Heather Chen-Mayer

    • NIST
    • NIST Center for Neutron Research, National Institute of Standards and Technology

  • Joseph Prestigiacomo

    • United States Naval Research Laboratory
    • NRL

  • Michael Osofsky

    • United States Naval Research Laboratory
    • NRL

  • Igor Smolyaninov

    • Saltenna LLC