Nature of magnetic excitations in the spin-1/2 triangular antiferromagnet Ba<sub>3</sub>CoSb<sub>2</sub>O<sub>9</sub> in applied magnetic field

ORAL

Abstract

Ba3CoSb2O9 is one of the very few experimental realizations of the spin-1/2 triangular antiferromagnets. Despite the model being extensively studied, a unified understanding of the compound’s zero-field magnetic excitations has not yet been achieved. Spin-wave theory up to 1/S correction clearly failed to describe the whole picture. However, whether this is indeed due to the intrinsic nature of the spin Hamiltonian remains debatable. Seeking more experimental evidence, we investigated the system’s field-induced states with inelastic neutron scattering, particularly in the low-field regime. While revealing some yet unexplained features, our results show some strong damping of the excitation branch around K point, consistent with the field-induced magnon decay scenario. Our results are expected to help obtain a better understanding the system.

*The work at Georgia Institute of Technology was supported by NSF-DMR-1750186. The work at University of Tennessee, Knoxville was supported by NSF-DMR-1350002.

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Presenters

  • Luwei Ge

    • School of Physics, Georgia Institute of Technology

Authors

  • Luwei Ge

    • School of Physics, Georgia Institute of Technology

  • Qing Huang

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

  • Tao Hong

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

  • 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

  • Jie Ma

    • Shanghai Jiao Tong University
    • Department of Physics and Astronomy, Shanghai Jiao Tong University

  • Martin Mourigal

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