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Magnetic vortex as a ground state for micron-scale antiferromagnetic samples

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 نشر من قبل Boris Ivanov A
 تاريخ النشر 2010
  مجال البحث فيزياء
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Here we consider micron-sized samples with any axisymmetric body shape and made with a canted antiferromagnet, like hematite or iron borate. We find that its ground state can be a magnetic vortex with a topologically non-trivial distribution of the sublattice magnetization $vec{l}$ and planar coreless vortex-like structure for the net magnetization $vec{M}$. For antiferromagnetic samples in the vortex state, in addition to low-frequency modes, we find high-frequency modes with frequencies over the range of hundreds of gigahertz, including a mode localized in a region of radius $sim$ 30--40 nm near the vortex core.



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