Understanding Stochastic Dynamics in Classical and Quantum Metastable Condensed Matter Systems

The noise-driven dynamics of three far-from-equilibrium systems are investigated: (i) transient dynamics in unstable potential and in Josephson junctions with Lévy noise; (ii) escape from a quantum dissipative metastable state in the presence of an external driving; (iii) the switching dynamics in a stochastic model of memristor.
We obtain: (i) exact analytical results of the residence time in the presence of Lévy flights in unstable potential profile, and noise enhanced stability phenomenon is observed in the system investigated and in JJs. (ii) a nonmonotonic behavior of the escape time versus the system-bath coupling, the temperature, and the frequency of the driving. The quantum noise enhanced stability phenomenon is observed in the system investigated. (iii) the nonstationary distribution and relaxation time of the stochastic model of memristors, which shows a nonmonotonic dependence, with a maximum, on the intensity of fluctuations.
References
[1] D. Valenti, A. Carollo, B. Spagnolo, Phys. Rev. A 97, 042109 (2018).
[2] C. Guarcello, D. Valenti, B. Spagnolo, V. Pierro, G. Filatrella, Phys. Rev. Applied, 11, 044078 (2019).
[3] N. V. Agudov, A. A. Dubkov, A. Krichigin, A. Safonov, B. Spagnolo “Role of noise in the switching dynamics of memristors”, preprint (2019).