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The role of Coulomb and exchange interaction on the Dzyaloshinskii-Moriya interaction(DMI) in BiFeO3

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 نشر من قبل Hong-Jian Feng
 تاريخ النشر 2012
  مجال البحث فيزياء
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 تأليف Hong-Jian Feng




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Ab initio calculations show that the Dzyaloshinskii-Moriya interaction(DMI)and net magnetization per unit cell in BiFeO3 are reduced when U is increasing from 0 to 2.9 eV, and independent of $J$. Interestingly, the DMI is even destroyed as $U$ exceeds a critical value of 2.9 eV. We propose a simple model to explain this phenomenon and present the nature of the rotation of the magnetization corresponding to altered antiferrodistortive distortions under DMI in BiFeO3.



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