0000000001335214
AUTHOR
Augello, Giuseppe
Dynamics of a FitzHugh-Nagumo system driven by a periodic signal in the presence of colored noise
We analyze the dynamics of a FitzHugh-Naguno system, driven by a periodic signal, in the presence of coloured noise. We consider the effects of the fluctuations by inserting in the deterministic FitzHugh-Nagumo model a term of additive Gaussian noise. We study the system in two different cases: the fluctuations affect the dynamics of the membrane potential (CASE I), the recovery variable is subjected to noise (CASE II). We review briefly the effects of the white noise, responsible for the appearance of resonant activation (RA) and noise enhanced stability (NES) phenomena. Afterwards we study the two cases in the presence of a coloured noise with correlation time tau. We investigate the effe…
Noise-induced phenomena in transient dynamics of short and long Josephson junctions
The investigation of nonlinear properties of Josephson junctions (JJs) is very important due to their broad applications in logic devices. Currently, all Josephson junctions are manufactured with the use of optical and electronic lithography, and they can always be considered as distributed. Moreover great interest recently has attracted, from theoretical and experimentally point of view, the investigation of the influence of thermal fluctuations in macroscopic quantum phenomena of short and long Josephson junctions. Particularly the role of the noise on the life time of the superconductive state has been subject of many investigations. In fact for some devices, as the rapid single flux qua…
Transient Dynamics of Short Josephson Junctions under the influence of non-Gaussian Noise
We investigate the effects of non-Gaussian white noise source on the transient dynamics of short Josephson junctions. The noise signal is simulated generating standard stable random variables with characteristic function described by Lévy index alpha and asymmetry parameter beta. We study the lifetime of the superconductive state as a function both of the frequency of the external driving bias current and the noise intensity for different values of index alpha. We compare our results with those obtained in the presence of Gaussian white noise. We find the presence of noise induced effects such as resonant activation and noise enhanced stability.