Direct measurement of antiferromagnetic domain fluctuations

ORAL

Abstract

We present coherent x-ray speckle measurements of slow nanoscale dynamics of domain walls separating microscopic regions with different orientations of the spin- (charge-) density waves in Cr bulk samples. Between 150K and 30K domain wall fluctuations slow down as the sample temperature is lowered, consistent with classical thermal activation model. Below 30K, however, the characteristic domain fluctuation timescale remains constant, possibly due to the cross-over between thermally activated and quantum tunneling mechanisms of domain wall relaxation.

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Authors

  • Oleg Shpyrko

    • Center for Nanoscale Materials, Argonne National Lab

  • Eric Isaacs

    • Center for Nanoscale Materials, Argonne National Lab

  • Jonathan Logan

    • University of Chicago

  • Hyekyung Kim

    • University of Chicago

  • Y. Feng

    • University of Chicago
    • James Franck Institute, University of Chicago

  • Rafael Jaramillo

    • University of Chicago
    • James Franck Institute, University of Chicago

  • T.F. Rosenbaum

    • University of Chicago
    • James Franck Institute, University of Chicago

  • Gabriel Aeppli

    • University College London

  • Paul Zschack

    • Argonne National Lab
    • Advanced Photon Source, Argonne National Lab

  • Michael Sprung

    • Advanced Photon Source, Argonne National Lab

  • Suresh Narayanan

    • Advanced Photon Source, Argonne, IL 60439
    • X-ray Science Division, Argonne National Lab, Argonne, IL 60439
    • Argonne National Laboratory
    • Advanced Photon Source, Argonne National Lab
    • X-ray Science Division, Argonne National Laboratory, Argonne, IL 60439
    • Argonne National Lab

  • Alec Sandy

    • Advanced Photon Source, Argonne, IL 60439
    • Advanced Photon Source, Argonne National Laboratory, Argonne, IL-60439, USA.
    • Advanced Photon Source, Argonne National Lab