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Field-induced magnetic phase transitions and the resultant giant anomalous Hall effect in antiferromagnetic half-Heusler DyPtBi

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 نشر من قبل Heda Zhang
 تاريخ النشر 2020
  مجال البحث فيزياء
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We report field-induced magnetic phase transitions and transport properties of antiferromagnetic DyPtBi. We show that DyPtBi hosts a delicate balance between two different magnetic ground states, which can be controlled by a moderate magnetic field. Furthermore, it exhibits giant anomalous Hall effect (sigma_A=1540 (ohm cm)^{-1},theta_{AHE} = 24%) in a field-induced Type-I spin structure, presumably attributed to the enhanced Berry curvature associated with avoided band-crossings near the Fermi energy and / or non-zero spin chirality. The latter mechanism points DyPtBi towards a rare potential realization of anomalous Hall effect in an antiferromagnet with face-center-cubic lattice that was proposed in [Physical Review Letters 87, 116801 (2001)].

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