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Ferromagnetic behavior of ultrathin manganese nanosheets

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 نشر من قبل Sreemanta Mitra
 تاريخ النشر 2012
  مجال البحث فيزياء
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Ferromagnetic behaviour has been observed experimentally for the first time in nanostructured Manganese. Ultrathin ($sim$ 0.6 nm) Manganese nanosheets have been synthesized inside the two dimensional channels of sol-gel derived Na-4 mica. The magnetic properties of the confined system are measured within 2K-300K temperature range. The confined structure is found to show a ferromagnetic behaviour with a nonzero coercivity value. The coercivity value remains positive throughout the entire temperature range of measurement. The experimental variation of susceptibility as a function of temperature has been satisfactorily explained on the basis of a two dimensional system with a Heisenberg Hamiltonian involving direct exchange interaction.



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