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Josephson-based threshold detector for Levy distributed fluctuations

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 نشر من قبل Claudio Guarcello
 تاريخ النشر 2018
  مجال البحث فيزياء
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We propose a threshold detector for Levy distributed fluctuations based on a Josephson junction. The Levy noise current added to a linearly ramped bias current results in clear changes in the distribution of switching currents out of the zero-voltage state of the junction. We observe that the analysis of the cumulative distribution function of the switching currents supplies information on both the characteristics shape parameter $alpha$ of the Levy statistics and the intensity of the fluctuations. Moreover, we discuss a theoretical model which allows to extract characteristic features of the Levy fluctuations from a measured distribution of switching currents. In view of this results, this system can effectively find an application as a detector for a Levy signal embedded in a noisy background.

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