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Quantitative analysis of the critical current due to vortex pinning by surface corrugation

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 نشر من قبل Docteur Alain Pautrat
 تاريخ النشر 2004
  مجال البحث فيزياء
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The transport critical current of a Niobium (Nb) thick film has been measured for a large range of magnetic field. Its value and variation are quantitatively described in the framework of the pinning of vortices due to boundary conditions at the rough surface, with a contact angle well explained by the spectral analysis of the surface roughness. Increasing the surface roughness using a Focused Ion Beam results also in an increase of the superficial critical current.



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