Spin Waves and Magnetic Interaction in the Multiferroic Antiferromagnet MnWO4

ORAL

Abstract

The spin wave excitations of the multiferroic MnWO4 have been measured in the low-temperature collinear commensurate phase using high-resolution inelastic scattering. The spin excitations can be well described by a Heisenberg model with competing exchange interactions up to 11th nearest neighbors. We find the magnetic exchange couplings are highly frustrated within each zigzag spin chain along c-axis and between chains along the a-axis. However, the magnetic interactions are much weaker between chains along the b-axis. Our measurements suggest that the delicate balance of long range magnetic couplings is subject to small perturbations that can lead to a complex magnetic configuration exhibiting magnetoelectric behavior.

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Authors

  • J.A. Fernandez-Baca

    • ORNL

  • Feng Ye

    • ORNL
    • Oak Ridge National Laboratory
    • Neutron Scattering Science Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA

  • R.S. Fishman

    • Materials Science and Technology Division, Oak Ridge National Laboratory, 37831 Oak Ridge, USA
    • Oak Ridge National Laboratory

  • A. Podlesnyak

    • ORNL

  • Georg Ehlers

    • NScD, Oak Ridge National Laboratory, 37831 Oak Ridge, USA
    • ORNL
    • Spallation Neutron Source, Oak Ridge National Laboratory

  • H.A. Mook

    • ORNL

  • Y.Q. Wang

    • Univ of Houston

  • Bernd Lorenz

    • Department of Physics and TcSUH at the University of Houston
    • Department of Physics, TcSUH, University of Houston
    • Univ of Houston
    • TCSUH and Department of Physics, University of Houston, Houston, Texas 77024-5002, USA
    • Dept. of Physics and TcSUH, University of Houston

  • Paul C. W. Chu

    • Texas Center for Superconductivity at University of Houston and Department of Physics,Lawrence Berkeley National Laboratory
    • Department of Physics and TcSUH at the University of Houston; Lawrence Berkeley National Laboratory
    • Department of Physics, TcSUH, University of Houston and Lawrence Berkeley National Laboratory
    • Dept. of Physics and Texas Center for Superconductivity, University of Houston, Houston, TX 77204-5002
    • Univ of Houston
    • TCSUH and Department of Physics, University of Houston, Houston, Texas 77024-5002, USA
    • Department of Physics and TcSUH, University of Houston
    • Dept. of Physics and TcSUH, University of Houston
    • Texas Center for Superconductivity, University of Houston and Lawrence Berkeley National Laboratory