Structural Disorder in the Quantum Spin-Liquid Candidate YbMgGaO<sub>4</sub>

ORAL

Abstract

The rare-earth oxide YbMgGaO4 is an exciting candidate for a quantum spin-liquid state based on a triangular lattice of Yb3+ ions. Experimental evidence for spin-liquid-like behavior includes a continuous magnetic excitation spectrum and the absence of long-range magnetic order to sub-100mK temperatures. Yet the origin of this behavior remains a subject for debate, with proposals ranging from resonating-valence-bond states and U(1) spin liquids, to disorder-induced mimicry of a quantum spin liquid. Disorder plays an intrinsic role in the structure of YbMgGaO4, because magnetic Yb3+ layers are separated by layers with disordered Mg2+/Ga3+ occupancy. In this talk, I will discuss experimental evidence for the importance of structural disorder in YbMgGaO4. Our X-ray and neutron scattering data reveal that structural disorder is not restricted to random Mg2+/Ga3+ occupancies, but is actually strongly correlated. I will explore the implications of our experimental results for the spin-liquid-like physics of YbMgGaO4.

*We acknowledge funding from Churchill College, Cambridge (JP), Georgia Tech's College of Sciences (MM, MD, ZLD, JP), Univ of Tennessee and NSF (ZLD, HDZ), and beamtime provison from STFC-ISIS, Diamond, and ORNL.

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Presenters

  • Joseph Paddison

    • School of Physics, Georgia Institute of Technology
    • University of Cambridge
    • Physics, Georgia Inst of Tech
    • Physics, University of Cambridge

Authors

  • Joseph Paddison

    • School of Physics, Georgia Institute of Technology
    • University of Cambridge
    • Physics, Georgia Inst of Tech
    • Physics, University of Cambridge

  • Marcus Daum

    • School of Physics, Georgia Institute of Technology
    • School of Physics, Georgia Tech

  • Zhiling Dun

    • Department of Physics and Astronomy, University of Tennessee
    • School of Physics, Georgia Institute of Technology
    • School of Physics, Georgia Tech
    • Georgia Institute of Technology
    • Physics, Georgia Institute of Technology
    • Physics, Georgia Inst of Tech

  • Arkadiy Simonov

    • Department of Chemistry, University of Oxford

  • Andrew Goodwin

    • Department of Chemistry, University of Oxford

  • Amber Thompson

    • Chemistry Research Laboratory, University of Oxford
    • Department of Chemistry, University of Oxford

  • Matthew Cliffe

    • University of Cambridge
    • Chemistry, University of Cambridge

  • Michael Gaultois

    • University of Cambridge
    • Chemistry, University of Cambridge

  • Helen Playford

    • STFC-ISIS

  • Yaohua Liu

    • Oak Ridge National Lab
    • Oak Ridge National Laboratory
    • Neutron Scattering Division, Oak Ridge National Lab

  • Haidong Zhou

    • Physics and Astronomy, Univ of Tennessee, Knoxville
    • Physics and Astronomy, University of Tennessee Knoxville
    • Department of Physics and Astronomy, University of Tennessee
    • Department of Physics and Astronomy, University of Tennessee Knoxville
    • Department of Physics & Astronomy, University of Tennessee
    • University of Tennessee
    • Physics and Astronomy, University of Tennessee
    • Physics, University of Tennessee
    • Univ of Tennessee, Knoxville
    • Physics and Astronomy, University of Tennessee, knoxville
    • Dept. of Physics and Astronomy, University of Tennessee

  • Martin Mourigal

    • School of Physics, Georgia Inst of Tech
    • School of Physics, Georgia Institute of Technology
    • School of Physics, Georgia Tech
    • Georgia Inst of Tech
    • Georgia Institute of Technology
    • Physics, Georgia Inst of Tech