Field induced spin density and spiral phases in a layered antiferromagnet

ORAL

Abstract

We will present neutron scattering measurements examining the low-field ordered magnetic phases of the $S=1$ dimerized antiferromagnet Ba$_3$Mn$_2$O$_8$. We have found that for magnetic both spin density wave order with incommensurate wave vectors and a higher field spiral phase with incommensurate wave vectors only along the $[hh0]$ direction. For both field induced ordered phases, the magnetic moments are lying in the plane perpendicular to the field direction. The nature of these two transitions is fundamentally different: the low-field transition is a second order transition to a spin-density wave ground state, while the one at higher field, toward the spiral phase, is of first order. More recent SANS measurements of the magnetic phases with H $||$ c will be presented if available at the time of the meeting.

*A portion of this research at ORNL was sponsored by the Scientific User Facilities Division, Office of Basic Energy Sciences, U.S. DOE. Work at Stanford supported by the NSF

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Authors

  • Matthew Stone

    • Oak Ridge NAtional Lab., TN, 37831
    • Quantum Condensed Matter Division, Oak Ridge National Laboratories
    • Quantum Condensed Matter Division, Oak Ridge National Laboratory
    • Oak Ridge National Laboratory
    • Spallation Neutron Source, Oak Ridge National Laboratory

  • Mark Lumsden

    • Quantum Condensed Matter Division, Oak Ridge National Laboratory
    • Quantum Condensed Matter Div., Oak Ridge National Laboratory, Oak Ridge, TN - 37830
    • Oak Ridge National Laboratory

  • V. O. Garlea

    • Quantum Condensed Matter Division, Oak Ridge National Laboratory
    • Oak Ridge National Lab

  • Beatrice Grenier

    • INAC-SPSMS, CEA & Universite Grenoble Alpes

  • Eric Ressouche

    • INAC-SPSMS, CEA & Universite Grenoble Alpes

  • Eric Samulon

    • Department of Applied Physics and Geballe Laboratory for Advanced Materials Stanford University

  • Ian R. Fisher

    • Department of Applied Physics and Geballe Laboratory for Advanced Materials Stanford University
    • Stanford University
    • Stanford

  • Lisa DeBeer-Schmitt

    • Oak Ridge National Lab, Oak Ridge, TN
    • Chemical & Engineering Materials Division, Oak Ridge National Laboratory
    • Oak Ridge National Laboratory (ORNL)
    • Oak Ridge National Lab

  • A. T. Hristov

    • Department of Applied Physics and Geballe Laboratory for Advanced Materials Stanford University
    • Stanford University

  • J.L. Gavilano

    • Paul Scherrer Institute, Villigen, Switzerland
    • Paul Scherrer Institute