Luttinger Quantum Paramagnet from Dimensional Recombination in the Frustrated Spin-1/2 Trimer Magnet Ba<sub>4</sub>Ir<sub>3</sub>O<sub>10</sub>

ORAL

Abstract

We report a highly frustrated spin state persisting down to 0.2 K in the monoclinic Ba4Ir3O10 with Ir4+(5d5) ions, which consists of Ir3O12 trimers of face-sharing IrO6 octahedra and wavy two-dimensional Ir-O sheets. This iridate conspicuously avoids any long-range magnetic order down to 0.2 K despite strong antiferromagnetic interaction with Curie-Weiss temperature -766 K. The corresponding frustration ratio reaches an astonishing value of 3830. This frustrated spin state is further evidenced by a sizable, linear heat capacity, indicating substantial residual entropy even at milli-Kelvin temperatures. It is equally striking that a mere 2% nonmagnetic Sr substitution for Ba readily lifts frustration and precipitates a long-range antiferromagnetic order at 130 K, suggesting proximity to a quantum critical point potentially with emergent random spin nucleation.

*This work was supported by the National Science Foundation via grant DMR-1712101.

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Presenters

  • Hengdi Zhao

    • Department of Physics, University of Colorado, Boulder CO 80309
    • Department of Physics, University of Colorado, Boulder, CO 80309
    • Department of Physics, University of Colorado at Boulder
    • University of Colorado, Boulder

Authors

  • Hengdi Zhao

    • Department of Physics, University of Colorado, Boulder CO 80309
    • Department of Physics, University of Colorado, Boulder, CO 80309
    • Department of Physics, University of Colorado at Boulder
    • University of Colorado, Boulder

  • Hao Zheng

    • Department of Physics, University of Colorado, Boulder CO 80309
    • Department of Physics, University of Colorado, Boulder, CO 80309
    • Department of Physics, University of Colorado at Boulder
    • University of Colorado, Boulder

  • Yifei Ni

    • Department of Physics, University of Colorado, Boulder CO 80309
    • Department of Physics, University of Colorado, Boulder, CO 80309

  • Yu Zhang

    • Department of Physics, University of Colorado, Boulder CO 80309
    • Department of Physics, University of Colorado, Boulder, CO 80309

  • Feng Ye

    • Quantum Condensed Matter Division, Oak Ridge National Laboratory
    • Neutron Scattering Division, Oak Ridge National LaboratoryOak Ridge, Tennessee 37381, USA
    • Quantum Condensed Matter Division, Oak Ridge National Laboratory, TN 37831
    • Oak Ridge National Laboratory
    • Neutron Scattering Division, Oak Ridge National Laboratory

  • Xiaoping Wang

    • Neutron Scattering Division, Oak Ridge National LaboratoryOak Ridge, Tennessee 37381, USA
    • Oak Ridge National Laboratory

  • Christina Hoffmann

    • Neutron Scattering Division, Oak Ridge National LaboratoryOak Ridge, Tennessee 37381, USA
    • Oak Ridge National Laboratory

  • Minhyea Lee

    • Department of Physics, University of Colorado, Boulder CO 80309

  • Itamar Kimchi

    • Department of Physics, University of Colorado, Boulder CO 80309
    • Center for Theory of Quantum Matter, University of Colorado, Boulder
    • Physics, University of Colorado, Boulder
    • University of Colorado at Boulder

  • Michael A Hermele

    • Department of Physics, University of Colorado, Boulder CO 80309
    • Physics, University of Colorado, Boulder
    • University of Colorado, Boulder

  • Gang Cao

    • Department of Physics, University of Colorado-Boulder
    • Department of Physics, University of Colorado, Boulder CO 80309
    • Department of Physics, University of Colorado, Boulder, CO 80309
    • Department of Physics, University of Colorado at Boulder
    • Physics and Astronomy, University of Kentucky
    • University of Colorado, Boulder
    • University of Colorado Boulder