Inelastic neutron scattering investigation of the geometrically frustrated honeycomb cobaltate BaCo<sub>2</sub>(AsO<sub>4</sub>)<sub>2</sub> in a transverse field

ORAL

Abstract

BaCo2(AsO4)2 is a honeycomb quantum magnet where an antiferromagnetic third nearest neighbor interaction frustrates nearest neighbor ferromagnetic easy plane interactions which may place the material close to a quantum spin-liquid phase. In particular, a field applied transverse to the honeycomb plane should enhance quantum fluctuations and might be able to induce a quantum spin-liquid.

To explore this possibility, we performed inelastic neutron scattering measurements in a large transverse field. By tilting the c-axis by five degrees relative to a large vertical field, a small in-plane field was applied along the nearest-neighbor bond direction. Even with 10.9 tesla along c and 1 tesla along a, commensurate antiferromagnetic order and coherent, gapped spin wave exciations were found at T=1.8 K. Analysis of the corresponding anisotropic dispersion relation was used to further constrain the spin Hamiltonian for BaCo2(AsO4)2, and gauge opportunities for realizing spin liquid phases in the honeycomb cobaltate.

*This work was supported as part of the Institute for Quantum Matter, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award No. DE-SC0019331 and by the Gordon Betty Moore Foundation under Award No. GBMF9456.

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Presenters

  • Thomas J Halloran

    • Johns Hopkins University

Authors

  • Thomas J Halloran

    • Johns Hopkins University

  • Tong Chen

    • Johns Hopkins Univ
    • Johns Hopkins University
    • Rice University

  • Austin M Ferrenti

    • Johns Hopkins University

  • Barry Winn

    • ORNL
    • Oak Ridge National Lab
    • Oak Ridge National Laboratory

  • Melissa K Graves-Brook

    • Oak Ridge National Lab
    • Oak Ridge National Laboratory

  • Robert Cava

    • Princeton University

  • Tyrel M McQueen

    • Johns Hopkins University
    • Cornell University
    • Department of Chemistry, Johns Hopkins University

  • Ruidan Zhong

    • Shanghai Jiao Tong Univ

  • Collin L Broholm

    • John Hopkins University
    • Johns Hopkins University