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Changes of Magnetism in a Magnetic Insulator due to Proximity to a Topological Insulator

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 نشر من قبل Tao Liu
 تاريخ النشر 2020
  مجال البحث فيزياء
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This letter reports the modification of magnetism in a magnetic insulator Y3Fe5O12 thin film by topological surface states (TSS) in an adjacent topological insulator Bi2Se3 thin film. Ferromagnetic resonance measurements show that the TSS in Bi2Se3 produces a perpendicular magnetic anisotropy, results in a decrease in the gyromagnetic ratio, and enhances the damping in Y3Fe5O12. Such TSS-induced changes become more pronounced as the temperature decreases from 300 K to 50 K. These results suggest a completely new approach for control of magnetism in magnetic thin films.

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