6533b883fe1ef96bd12de4a3

RESEARCH PRODUCT

Analysis of soliton dynamics and noise induced effects on the superconductive lifetime in long Josephson junctions.

Claudio Guarcello

subject

Lévymean escape timesine-GordonJosephson junctionJosephson junction; sine-Gordon; washboard; Lévy; Gaussian noise; non-Gaussian noise; soliton; breather; mean escape time; noise enhanced stability; resonant activationbreatherwashboardresonant activationGaussian noisesolitonSettore FIS/03 - Fisica Della Materianon-Gaussian noisenoise enhanced stability

description

The influence of various noise sources on the transient dynamics of long Josephson junctions (LJJ) is investigated in the presence of an oscillating bias current signal and a noise source with Gaussian or non-Gaussian (i.e. Cauchy-Lorentz or Lévy-Smirnov) probability distributions. These systems are computationally analyzed integrating the perturbed Sine-Gordon equation describing the phase evolution. We found evidence of noise induced effects on trends of the mean escape time (MET) from the superconductive metastable state, varying different system parameters, as the bias frequency, noise intensity and junction length. In particular, we find resonant activation (RA) and noise enhanced stability (NES), and we study the connections between these phenomena and the creation/evolution of solitons (i.e. kink and antikink solutions) in the LJJ phase string dynamics. Pronounced changes in RA and NES are observed by using Lévy noise sources with different statistics. MET is also studied considering spatially homogeneous and inhomogeneous bias current distributions. In the latter case, in the presence of Gaussian noise, we observe an enhanced non-monotonic behavior, that, conversely, almost vanishes using noise sources with different statistics.

yearjournalcountryeditionlanguage
2013-09-01
http://hdl.handle.net/10447/83743