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Discontinuity of capacitance at the onset of surface superconductivity

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 Added by Klaus Morawetz
 Publication date 2008
  fields Physics
and research's language is English




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The effect of the magnetic field on a capacitor with a superconducting electrode is studied within the Ginzburg-Landau approach. It is shown that the capacitance has a discontinuity at the onset of the surface superconductivity $B_{rm c3}$ which is expressed as a discontinuity in the penetration depth of the electric field into metals. Estimates show that this discontinuity is observable with recent bridges for both conventional and high-$T_{rm c}$ superconductors of the type-II.



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