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Magnetic Control of Ferroelectric Polarization in a Self-formed Single Magnetoelectric Domain of Multiferroic Ba3NbFe3Si2O14

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 نشر من قبل Nara Lee
 تاريخ النشر 2014
  مجال البحث فيزياء
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We have discovered strong magnetoelectric (ME) effects in the single chiral-helical magnetic state of single-crystalline langasite Ba3NbFe3Si2O14 that is crystallographically chiral. The ferroelectric polarization, predominantly aligned along the a axis below the Neel temperature of ~27 K, changes in a highly non-linear fashion in the presence of in-plane magnetic fields (H) perpendicular to the a axis (H//b*). This ME effect as well as smaller ME effects in other directions exhibit no poling dependence, suggesting the presence of a self-formed single ME domain. In addition, these ME effects accompany no-measurable hysteresis, which is crucial for many technological applications.

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