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Asymmetric noise probed with a Josephson junction

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 نشر من قبل Hugues Pothier
 تاريخ النشر 2009
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Q. Le Masne




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Fluctuations of the current through a tunnel junction are measured using a Josephson junction. The current noise adds to the bias current of the Josephson junction and affects its switching out of the supercurrent branch. The experiment is carried out in a regime where switching is determined by thermal activation. The variance of the noise results in an elevated effective temperature, whereas the third cumulant, related to its asymmetric character, leads to a difference in the switching rates observed for opposite signs of the current through the tunnel junction. Measurements are compared quantitatively with recent theoretical predictions.



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