Orbital-selective correlations and superconductivity in the nematic FeSe

 · Invited

Abstract

The interplay between electronic orders, orbital-selective electronic correlations and associated superconductivity, has played a central role in the physics of emergent phases and unconventional superconductivity. This interplay has been found to be particularly pronounced in recently discovered iron-based superconductors. Motivated by the recent low-temperature experiments on iron selenide (FeSe), we theoretically study the electronic correlation effects and emerging superconductivity in a multiorbital model for this compound. We propose that the combination of various bond nematic orders with the ferro-orbital order can give rise to a surprisingly large orbital selectivity among the Fe-3d t2g orbitals in the normal state. This enhanced orbital selectivity is also reflected in the superconducting pairing amplitudes, which gives rise to a large gap anisotropy on the Fermi surface. Our results naturally explain the seemingly unusual observation of strong orbital selectivity and related unconventional superconductivity in the nematic phase of FeSe, thereby providing new insight into the nature of both the nematic order and the iron-based superconductivity in general.

*This work has in part been supported by the National Science Foundation of China Grant numbers 11674392 and Ministry of Science and Technology of China, National Program on Key Research Project Grant number 2016YFA0300504 (R.Y.), and by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, under Award No. DE-SC0018197, the Robert A. Welch Foundation Grant No. C-1411 and a QuantEmX grant from ICAM and the Gordon and Betty Moore Foundation through Grant No. GBMF5305 (Q.S.), and by the U.S. DOE Office of Basic Energy Sciences E3B5 (J.-X.Z.).

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Presenters

  • Jian-Xin Zhu

    • Theoretical Division, Los Alamos National Laboratory
    • Los Alamos National Laboratory
    • Theoretical Division and Center for Integrated Nanotechnologies, Los Alamos National Laboratory
    • T4-PHYS OF CONDENSED MATTER & COMPLEX SYS, Los Alamos National Laboratory, Los aAlamos, USA
    • CINT, Los Alamos National Laboratory
    • Center for Integrated Nanotechnologies, Los Alamos National Laboratory
    • Los Alamos National Laboratory,

Authors

  • Jian-Xin Zhu

    • Theoretical Division, Los Alamos National Laboratory
    • Los Alamos National Laboratory
    • Theoretical Division and Center for Integrated Nanotechnologies, Los Alamos National Laboratory
    • T4-PHYS OF CONDENSED MATTER & COMPLEX SYS, Los Alamos National Laboratory, Los aAlamos, USA
    • CINT, Los Alamos National Laboratory
    • Center for Integrated Nanotechnologies, Los Alamos National Laboratory
    • Los Alamos National Laboratory,

  • Haoyu Hu

    • Rice University
    • Department of Physics and Astronomy, Rice University

  • Rong Yu

    • Renming University of China
    • Physics Department, Renmin University
    • Renmin University of China
    • Department of Physics, Renmin University of China

  • Emilian Nica

    • University of British Columbia
    • Department of Physics, Arizona State University
    • Department of Physics and Astronomy, University of British Columbia
    • Arizona State University

  • Qimiao Si

    • Rice University
    • Department of Physics and Astronomy, Rice University
    • Department of Physics and Astronomy, Houston, Texas 77005, USA, Rice University