STM/STS study of superconducting properties modified by Ca deposition on Ca<sub>10</sub>(Pt<sub>4</sub>As<sub>8</sub>)(Fe<sub>2</sub>As<sub>2</sub>)<sub>5</sub>

ORAL

Abstract

Ca10(Pt4As8)(Fe2As2)5 contains both superconducting building blocks (Fe2As2 layers) and conducting spacers (Pt4As8 layers), unlike insulating spacers in other Fe-based superconductors. Prior work showed the important role played by the charge environment and surface structures in its superconducting properties: evidence for superconductivity is absent in bare Pt4As8 surface but recovers when Ca atoms are atop [1]. Different surface reconstructions also lead different superconducting features. We use scanning tunneling microscopy and spectroscopy (STM/S) to directly confirm the role of charge balance and surface structures on superconductivity in this compound. Cleaving provides large areas of bare Pt4As8 layer, which originally does not show superconducting features. Depositing additional Ca atoms on the bare Pt4As8 surface, while the sample is on the STM scanning stage, results in changes in spectral features. We will discuss the relationship between surface structures and superconducting features based on the Ca structures formed by controlling the deposition temperature.
[1] J. Kim et al., Sci. Rep. 6, 35365 (2016).

*Funded by NSERC, CFREF, USNSF

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Presenters

  • Jisun Kim

    • Stewart Blusson Quantum Matter Institute, University of British Columbia
    • University of British Columbia

Authors

  • Jisun Kim

    • Stewart Blusson Quantum Matter Institute, University of British Columbia
    • University of British Columbia

  • Seokhwan Choi

    • Stewart Blusson Quantum Matter Institute, University of British Columbia
    • University of British Columbia

  • Brandon Stuart

    • Stewart Blusson Quantum Matter Institute, University of British Columbia
    • University of British Columbia

  • Amy Qu

    • University of British Columbia
    • Stewart Blusson Quantum Matter Institute, University of British Columbia

  • Silu Huang

    • Louisiana State University
    • Department of Physics and Astronomy, Louisiana State University

  • Rongying Jin

    • Louisiana State University
    • Physics, Louisiana State University
    • Physics and astronomy, Louisiana State University
    • 2Condensed Matter Physics and Materials Science Departement, Brookhaven National Laboratory
    • Department of Physics and Astronomy, Louisiana State University
    • Physics and Astronomy, Louisiana State University

  • Douglas Bonn

    • Stewart Blusson Quantum Matter Institute
    • University of British Columbia
    • Stewart Blusson Quantum Matter Institute, University of British Columbia
    • Quantum Matter Institute, University of British Columbia

  • Sarah A. Burke

    • Department of Physics and Astronomy, University of British Columbia
    • University of British Columbia
    • Stewart Blusson Quantum Matter Institute, University of British Columbia