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Competition between electronic cooling and Andreev dissipation in a superconducting micro-cooler

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 نشر من قبل Herve Courtois
 تاريخ النشر 2009
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Sukumar Rajauria




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We discuss very low temperature experiments on superconducting micro-coolers made of a double Normal metal - Insulator - Superconductor junction. We investigate with a high resolution the differential conductance of the micro-cooler as well as of additional probe junctions. There is an explicit crossover between the single quasi-particle current and the phase-coherent Andreev current. We establish a thermal model by considering the thermal contribution due to the Andreev current. The related increase of the electron temperature is discussed, including the influence of several parameters like the phase-coherence length or the tunnel junction transparency.



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