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Resistivity Minimum in Granular Composites and Thin Metallic Films

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 نشر من قبل Alexander Gerber
 تاريخ النشر 2016
  مجال البحث فيزياء
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We analyze the temperature dependence of conductivity in thick granular ferromagnetic compounds NiSiO2 and in thin weakly coupled films of Fe, Ni and Py in vicinity of metal-insulator transition. Development of resistivity minimum followed by a logarithmic variation of conductivity at lower temperatures is attributed to granular structure of compounds and thin films fabricated by conventional deposition techniques. Resistivity minimum is identified as a transition between temperature dependent intra-granular metallic conductance and thermally activated inter-granular tunneling.



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