Le Masne Q, Pothier H, Birge Norman O, Urbina C, Esteve D
Quantronics group, Service de Physique de l'Etat Condensé (CNRS URA 2464), CEA-Saclay, 91191 Gif-sur-Yvette, France.
Phys Rev Lett. 2009 Feb 13;102(6):067002. doi: 10.1103/PhysRevLett.102.067002. Epub 2009 Feb 10.
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.
