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Enhancement of magnetic ordering by the stress fields of grain boundaries in ferromagnets

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 نشر من قبل Anatoli Kadigrobov
 تاريخ النشر 2001
  مجال البحث فيزياء
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In the paper we predict a distinctive change of magnetic properties and considerable increase of the Curie temperature caused by the strain fields of grain boundaries in ferromagnetic films. It is shown that a sheet of spontaneous magnetization may arise along a grain boundary at temperatures greater than the bulk Curie temperature. The temperature dependence and space distribution of magnetization in a ferromagnetic film with grain boundaries are calculated. We found that $45^circ$ grain boundaries can produce long-range strain fields that results in the width of the magnetic sheet along the boundary of the order of $ 0.5 div 1 mu m$ at temperatures grater than the bulk Curie temperature by about $10^2$ K.



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