Disorder Driven Mott Gap Collapse accompanied by the Emergence of a Pseudogap

ORAL

Abstract

The origin of the pseudogap in doped Mott insulators remains one of the biggest mysteries in correlated electron systems. Of the potential causes for a pseudogap, disorder, while ubiquitous, is least invoked and most poorly understood. To investigate the role of disorder in destabilizing a Mott state and realizing a pseudogap state, we use scanning tunneling microscopy and spectroscopy to study isovalent Ru substitutions in Sr3(Ir1-xRux)2O7 (0≤x≤0.5). Ru creates disorder without the complication of additional order parameters and drives the insulator into an antiferromagnetic, metallic state with a pseudogap similar to that seen in other iridates and cuprates. Nanoscale data show that disorder mediates the transition by locally collapsing the Mott gap and this effect can be captured by a minimal Mott-Hubbard model. Our work establishes a novel mechanism for an insulator to metal transition and establishes a central role for disorder in realizing an emergent pseudogap state in doped Mott systems.

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Presenters

  • Zhenyu Wang

    • University of Illinois - Urbana Champaign
    • Physics, University of Illinois
    • Physics, Univeristy of Illinois at Urbana-Champaign
    • Univ of Illinois - Urbana
    • Department of Physics, University of Illinois
    • Physics, Univ of Illinois - Urbana
    • Department of Physics, Univ of Illinois - Urbana-Champaign

Authors

  • Zhenyu Wang

    • University of Illinois - Urbana Champaign
    • Physics, University of Illinois
    • Physics, Univeristy of Illinois at Urbana-Champaign
    • Univ of Illinois - Urbana
    • Department of Physics, University of Illinois
    • Physics, Univ of Illinois - Urbana
    • Department of Physics, Univ of Illinois - Urbana-Champaign

  • Yoshinori Okada

    • Advanced Institute for Materials Research (AIMR), , Tohoku University
    • Tohoku University

  • Jared O’ Neal

    • The Ohio State University

  • Wenwen Zhou

    • Boston College
    • Department of Physics, Boston College

  • Daniel Walkup

    • NIST
    • National Institute of Standards and Technology
    • CNST, NIST

  • Chetan Dhital

    • Boston College

  • Tom Hogan

    • University of California
    • Materials Department, UCSB
    • Univ of California - Santa Barbara

  • Patrick Clancy

    • Trent University
    • Department of Physics, University of Toronto
    • University of Toronto

  • Young-June Kim

    • Physics, University of Toronto
    • Department of Physics, University of Toronto
    • University of Toronto

  • Luiz Santos

    • Physics, Univ of Illinois - Urbana
    • Univ of Illinois - Urbana

  • Stephen Wilson

    • Materials, University of California, Santa Barbara
    • Materials Department, University of California, Santa Barbara
    • University of California
    • University of California, Santa Barbara
    • Materials Department, UCSB

  • Nandini Trivedi

    • Department of Physics, The Ohio State University
    • The Ohio State University

  • Vidya Madhavan

    • Physics, Univ of Illinois - Urbana
    • Physics, Univ of Illinois
    • University of Illinois - Urbana Champaign
    • Physics, University of Illinois
    • University of Illinois at Urbana-Champaign
    • Physics, Univeristy of Illinois at Urbana-Champaign
    • Univ of Illinois - Urbana
    • Department of Physics, University of Illinois
    • Department of Physics, Univ of Illinois - Urbana-Champaign