Manifestly Non-Gaussian Fluctuations in Superconductor-Normal Metal Tunnel Nanostructures

We propose a mesoscopic setup which exhibits strong and manifestly non-Gaussian fluctuations of energy and temperature when suitably driven out of equilibrium. The setup consists of a normal metal island (N) coupled by tunnel junctions (I) to two superconducting leads (S), forming a SINIS structure, and is biased near the threshold voltage for quasiparticle tunneling, eV?2?. The fluctuations can be measured by monitoring the time-dependent electric current through the system. This makes the setup suitable for the realization of feedback schemes which can be used to stabilize the temperature to the desired value