Mapping magnetism with atomic resolution using aberrated electron probes

ORAL

Abstract

In this talk, we report a direct experimental real-space mapping of magnetic circular dichroism with atomic resolution in aberration-corrected scanning transmission electron microscopy (STEM). Using an aberrated electron probe with customized phase distribution, we reveal with electron energy-loss (EEL) spectroscopy the checkerboard antiferromagnetic ordering of Mn moments in LaMnAsO by observing a dichroic signal in the Mn L-edge. The aberrated probes allow the collection of EEL spectra using the transmitted beam, which results in a magnetic circular dichroic signal with intrinsically larger signal-to-noise ratios than those obtained via nanodiffraction techniques (where most of the transmitted electrons are discarded). The novel experimental setup presented here, which can easily be implemented in aberration-corrected STEM, opens new paths for probing dichroic signals in materials with unprecedented spatial resolution.

*This research was supported by DOE SUFD MSED, by UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 with the US DOE, and by the Swedish Research Council and Swedish National Infrastructure for Computing (NSC center)

Authors

  • Juan Idrobo

    • Oak Ridge National Laboratory
  • Jan Rusz

    • Uppsala University
    • Department of Physics and Astronomy, Uppsala University, Uppsala
  • Michael A. McGuire

    • Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
    • Oak Ridge National Laboratory
  • Christopher T. Symons

    • Oak Ridge National Laboratory
  • Ranga Raju Vatsavai

    • Oak Ridge National Laboratory
  • Andrew R. Lupini

    • Oak Ridge National Laboratory