Josephson-based Threshold Detector for Lévy-Distributed Current Fluctuations

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. Moreover, we discuss a theoretical model, which allows characteristic features of the Levy fluctuations to be extracted from a measured distribution of switching currents. In view of these results, this system can effectively find an application as a detector for a Levy signal embedded in a noisy background.