Josephson-based threshold detector for Lévy distributed fluctuations

Abstract

We propose a threshold detector for Lévy distributed fluctuations based on a Josephson junction. The Lévy 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 $α$ of the Lévy statistics and the intensity of the fluctuations. Moreover, we discuss a theoretical model which allows to extract characteristic features of the Lévy 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 Lévy signal embedded in a noisy background.

9 pages, 3 figures