Lifetime of the superconductive state in short and long Josephson junctions

TL;DR

This paper investigates the effects of thermal and correlated noise on the lifetime of the superconductive state in short and long Josephson junctions, revealing noise-induced phenomena and nonmonotonic behaviors.

Contribution

It provides a detailed analysis of noise effects on Josephson junctions' lifetime, including the influence of correlated noise and junction length, with numerical and theoretical insights.

Findings

Noise induces nonmonotonic lifetime behavior.

Presence of two maxima in escape time with correlated noise.

Lifetime depends on current frequency and noise parameters.

Abstract

We study the transient statistical properties of short and long Josephson junctions under the influence of thermal and correlated fluctuations. In particular, we investigate the lifetime of the superconductive metastable state finding the presence of noise induced phenomena. For short Josephson junctions we investigate the lifetime as a function both of the frequency of the current driving signal and the noise intensity and we find how these noise-induced effects are modified by the presence of a correlated noise source. For long Josephson junctions we integrate numerically the sine-Gordon equation calculating the lifetime as a function of the length of the junction both for inhomogeneous and homogeneous bias current distributions. We obtain a nonmonotonic behavior of the lifetime as a function of the frequency of the current driving signal and the correlation time of the noise. Moreover we find two maxima in the nonmonotonic behaviour of the mean escape time as a function of the correlated noise intensity.