Thickness dependent study of superconducting behavior and contact dynamics in atomically thin Fe(Te<sub>0.7</sub>Se<sub>0.3</sub>) Flakes

ORAL

Abstract

We present evidence of thickness dependent superconducting behavior in strain-free Fe(Te0.7Se0.3) flakes. Due to non-uniform Te/Se spatial distribution, we find that R(T) behavior in flakes <10nm can be explained and confirmed using the BKT transition for inhomogeneity model, as well as finite state effects(FSE). For >10nm flakes we find a systematic suppression of the superconductivity and broadening of the superconducting phase transition. Additionally, we present a self-heating model at the metal-superconductor-metal(MSM) interface to explain unusual observed switching behavior in I-V characteristicsfor flakes thinner than 10nm. We propose a 2D network of superconducting paths connecting superconducting islands within Fe(Te0.7Se0.3) thin flakes to describe the thickness-dependent behavior of this natural percolating system.

*This work was supported by the DOE under grant DESC0014208 and by the Board of Regents Support Fund (BoRSF) under grant LEQSF(2015-18)-RD-A-23.

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Presenters

  • Andrew Steely

    • Tulane Univ

Authors

  • Andrew Steely

    • Tulane Univ

  • Chunlei Yue

    • Tulane Univ

  • Yun Ling

    • Tulane Univ

  • Abin Joshy

    • Tulane Univ

  • Zhiqiang Mao

    • Pennsylvania State University
    • Tulane University
    • Physics, Pennsylvania State University
    • Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802, USA
    • Physics, The Pennsylvania State University
    • Department of Physics, Pennsylvania State University
    • Penn State University
    • Physics, Penn State University
    • The Pennsylvania State University

  • Jiang Wei

    • Tulane Univ