Terahertz investigation of strong coupling between metamaterials and superconducting Josephson plasmons in La<sub>2-x</sub>Sr<sub>x</sub>CuO<sub>4</sub>

ORAL

Abstract

We investigate the coupling between an array of metamaterial resonators and the Josephson Plasma Resonance (JPR) in superconducting La2-xSrxCuO4 (LSCO) using terahertz (THz) time domain spectroscopy. This is accomplished by adhering metamaterial “tapes” to the surface of an LSCO single crystal with the c-axis in-plane. We are able to repeatably bring the resonators within ~1um of the LSCO surface. The resulting electrodynamic response is measured as a function of temperature and resonator-surface distance, essentially changing the coupling strength. In the superconducting state, coupling between the metamaterial mode and the JPR renormalizes the JPR frequency, suggestive of a large modification of the superconducting state. The nonlinear response, measured with THz fields up to approximately 100kV/cm is consistent with strong-coupling induced modification of superconductivity as such measurements also exhibit plasma edge renormalization with increasing field strength.

*Research at UCSD funded by Department of Energy Basic Energy Sciences DE-SC0018218 and ARO Award No. W911NF-16-1-0361. Research at BU supported by National Science Foundation under Grant No. ECCS-1810252.

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Presenters

  • Kelson Kaj

    • University of California San Diego
    • Physics, University of California San Diego
    • Department of Physics, University of California, San Diego
    • University of California, San Diego

Authors

  • Kelson Kaj

    • University of California San Diego
    • Physics, University of California San Diego
    • Department of Physics, University of California, San Diego
    • University of California, San Diego

  • Ian Newton Hammock

    • University of California, San Diego

  • Chunxu Chen

    • Boston University
    • Mechanical Engineering, Boston University

  • Xiaoguang Zhao

    • Boston University
    • Mechanical Engineering, Boston University

  • Kevin A Cremin

    • Department of Physics, University of California, San Diego
    • University of California, San Diego

  • Michael Fogler

    • University of California, San Diego
    • Department of Physics, University of California San Diego
    • UC San Diego
    • Department of Physics, University of California, San Diego
    • UCSD
    • University of California San Diego

  • Dmitri Basov

    • Columbia University
    • Department of Physics, Columbia University
    • Physics, Columbia University
    • Columbia Univ

  • Xin Zhang

    • Boston University
    • Mechanical Engineering, Boston University

  • Richard Averitt

    • University of California, San Diego
    • University of California San Diego
    • UC San Diego
    • Physics, University of California San Diego
    • Department of Physics, University of California, San Diego
    • University of California