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Re-entrance of the metallic conductance in a mesoscopic proximity superconductor

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 نشر من قبل ul
 تاريخ النشر 1996
  مجال البحث فيزياء
والبحث باللغة English
 تأليف P. Charlat




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We present an experimental study of the diffusive transport in a normal metal near a superconducting interface, showing the re-entrance of the metallic conductance at very low temperature. This new mesoscopic regime comes in when the thermal coherence length of the electron pairs exceeds the sample size. This re-entrance is suppressed by a bias voltage given by the Thouless energy and can be strongly enhanced by an Aharonov Bohm flux. Experimental results are well described by the linearized quasiclassical theory.



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