Quantum phase transition of correlated iron-based superconductivity in LiFe<sub>1-x</sub>Co<sub>x</sub>As

ORAL

Abstract

We use scanning tunneling microscopy (STM) to image the electronic impact of Co atoms on the ground state of the LiFe1-xCoxAs system. We observe that impurities progressively suppress the global superconducting gap and introduce low energy states near the gap edge, with the superconductivity remaining in the strong-coupling limit. Unexpectedly, the fully opened gap evolves into a nodal state before the Cooper pair coherence is fully destroyed. Our systematic theoretical analysis shows that these new observations can be quantitatively understood by the nonmagnetic Born-limit scattering effect in a s±-wave superconductor, unveiling the driving force of the superconductor to metal quantum phase transition.

*Experimental and theoretical work at Princeton University was supported by the Gordon and Betty Moore Foundation (GBMF4547/ Hasan) and the United States Department of energy (US DOE) under the Basic Energy Sciences programme (grant number DOE/BES DE-FG-02-05ER46200).

–

Presenters

  • Nana Shumiya

    • Princeton University
    • Physics, Princeton University

Authors

  • Nana Shumiya

    • Princeton University
    • Physics, Princeton University

  • Jiaxin Yin

    • Laboratory for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University
    • Princeton University
    • Physics, Princeton University

  • Songtian Sonia Zhang

    • Princeton University
    • Physics, Princeton University

  • Guangyang Dai

    • Institute of Physics, Chinese Academy of Sciences

  • Yuanyuan Zhao

    • School of Physics and Optoelectronic Engineering, Nanjing University of Information Science and Technology

  • Andreas Kreisel

    • Institute for Theoretical Physics, University of Leipzig
    • Universität Leipzig
    • University of Leipzig
    • Institut für Theoretische Physik, Universität

  • Gennevieve Macam

    • National Sun Yat-Sen University

  • Brian M. Andersen

    • University of Copenhagen
    • Niels Bohr Institute

  • Feng-Chuan Chuang

    • Department of Physics, National Sun Yat-sen University
    • Physics, National Sun Yat-Sen University
    • Natl Sun Yat Sen Univ
    • National Sun Yat-Sen University
    • Physics, National Sun Yat-sen University

  • Hsin Lin

    • Academia Sinica
    • Physics, Academia Sinica
    • Institute of Physics, Academia Sinica, Taipei, Taiwan
    • Institute of Physics, Academia Sinica

  • Ziqiang Wang

    • Boston College
    • Department of Physics, Boston College
    • Physics, Boston College

  • Changqing Jin

    • Chinese Academy of Sciences
    • EX5, Institute of Physics, Chinese Academy of Sciences
    • Institute of Physics, Chinese Academy of Sciences

  • Yunkyu Bang

    • Pohang University of Science and Technology, Pohang, Korea
    • Asia Pacific Center for Theoretical Physics and Department of Physics, POSTECH

  • Zahid Hasan

    • Laboratory for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University
    • Princeton University
    • Physics, Princeton University