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Planar Hall effect in antiferromagnetic MnTe thin films

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 نشر من قبل Gen Yin
 تاريخ النشر 2018
  مجال البحث فيزياء
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We show that the spin-orbit coupling (SOC) in alpha-MnTe impacts the transport behavior by generating an anisotropic valence-band splitting, resulting in four spin-polarized pockets near Gamma. A minimal k-dot-p model is constructed to capture this splitting by group theory analysis, a tight-binding model and ab initio calculations. The model is shown to describe the rotation symmetry of the zero-field planer Hall effect (PHE). The upper limit of the PHE percentage is shown to be fundamentally determined by the band shape, and is quantitatively estimated to be roughly 31% by first principles.



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