Luttinger Quantum Paramagnet from Dimensional Recombination in the Frustrated Spin-1/2 Trimer Magnet Ba4Ir3O10

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.

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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