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Unusual magnetic behavior in ferrite hollow nanospheres

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 نشر من قبل Roberto Zysler
 تاريخ النشر 2008
  مجال البحث فيزياء
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We report unusual magnetic behavior in iron oxide hollow nanospheres of 9.3 $nm$ in diameter. The large fraction of atoms existing at the inner and outer surfaces gives rise to a high magnetic disorder. The overall magnetic behavior can be explained considering the coexistence of a soft superparamagnetic phase and a hard phase corresponding to the highly frustrated cluster-glass like phase at the surface regions.



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