Interplay of charge and spin degrees of freedom in Mo3O13 cluster Mott insulators

 · Invited

Abstract

A promising approach to understanding the complexities of experimental quantum spin liquid candidates is to search for a way to tune the microscopic Hamiltonian and study changes in the resulting magnetic phases. In this talk I will present recent developments in a new class of highly tunable Mo3O13 cluster Mott insulators. This family of materials can be viewed as a breathing kagome lattice (BKL) of Mo ions, where the corner-sharing up and down triangles have two different sizes. In the compounds Li2In1-xScxMo3O8 the breathing parameter (λ) changes non-monotonically with Sc concentration (x), tuning the system from an antiferromagnetic Mott insulator for large λ, to a quantum spin liquid for small λ [1]. For large breathing parameter electrons become confined on the small triangles forming spin-1/2 Mo3 clusters on a triangular lattice with antiferromagnetic exchange coupling between them, leading to long range antiferromagnetic order. On the other hand, for small breathing parameter electrons are no longer confined to individual Mo3 clusters but can tunnel between adjacent clusters, leading to a novel long range plaquette charge order (PCO) [2]. Our thermodynamic and muon spin rotation (μSR) measurements, suggest that the PCO coincides with a high degree of spin frustration and leads to a quantum spin liquid ground state, with gapless spinon excitations. The tunability of these materials can be extended to lower and higher breathing parameter in several related Mo-oxide materials, revealing additional quantum spin liquids and even ferromagnetism.

[1] A. Akbari-Sharbaf et al., Phys. Rev. Lett. 120, 227201 (2018).
[2] G. Chen et al., Phys. Rev. B 93, 245134 (2016).

*We acknowledge funding from CFREF, NSERC, and FRQNT

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Presenters

  • Arash Akbari-Sharbaf

    • Department of Physics, Institut Quantique, Université de Sherbrooke, Sherbrooke, QC
    • Institut Quantique and Département de Physique, Université de Sherbrooke
    • Département de Physique, Université de Sherbrooke, Sherbrooke, QC, Canada

Authors

  • Arash Akbari-Sharbaf

    • Department of Physics, Institut Quantique, Université de Sherbrooke, Sherbrooke, QC
    • Institut Quantique and Département de Physique, Université de Sherbrooke
    • Département de Physique, Université de Sherbrooke, Sherbrooke, QC, Canada

  • Ryan P Sinclair

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

  • Aimé Verrier

    • Department of Physics, Institut Quantique, Université de Sherbrooke, Sherbrooke, QC
    • Institut Quantique and Département de Physique, Université de Sherbrooke
    • Institut Quantique, Université de Sherbrooke

  • Djamel Ziat

    • Institut Quantique and Département de Physique, Université de Sherbrooke

  • Haidong Zhou

    • University of Tennessee
    • Department of Physics and Astronomy, University of Tennessee
    • University of Tennessee, Knoxville
    • Physics, University of Tennessee, Knoxville, TN, United States
    • Physics, University of Tennessee
    • Department of Physics and Astronomy, The University of Tennessee, Knoxville
    • Department of Physics and Astronomy, University of Tennessee, Knoxville
    • Department of Physics, University of Tennessee

  • Xuefeng Sun

    • Department of Physics, Hefei National Laboratory for Physical Sciences at the Microscale

  • Jeffrey Quilliam

    • Department of Physics, Institut Quantique, Université de Sherbrooke, Sherbrooke, QC
    • Institut Quantique and Département de Physique, Université de Sherbrooke
    • Institut Quantique, Université de Sherbrooke
    • Universite de Sherbrooke
    • Département de Physique, Université de Sherbrooke, Sherbrooke, QC, Canada