Search results for "METASTABILITY"

showing 2 items of 262 documents

Metastability and Relaxation in Quantum and Mesoscopic Systems

2013

The transient dynamics and the relaxation of three quantum and mesoscopic systems are investigated. In particular we analyze: (i) a long Josephson junction (LJJ) driven by a non-Gaussian Lévy noise current; (ii) a metastable quantum dissipative system driven by an external periodical driving; and (iii) the electron spin relaxation process in n-type GaAs crystals driven by a fluctuating electric field. Specifically, in the first system the LJJ phase evolution is described by the perturbed sine-Gordon equation. We find the noise enhanced stability and resonant activation phenomena, by investigating the mean escape time as a function of the bias current frequency, noise intensity and length of…

Mesoscopic SystemMetastabilityRelaxationquantum dissipative systemelectron spin relaxationJosephson junctionMonte CarloMetastability; Relaxation; Mesoscopic System; Josephson junction; Lévy noise; quantum dissipative system; electron spin relaxation; Monte Carlo;Settore FIS/03 - Fisica Della MateriaLévy noise
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Nonlinear relaxation in quantum and mesoscopic systems

2013

The nonlinear relaxation of three mesoscopic and quantum systems are investigated. Specifically we study the nonlinear relaxation in: (i) a long Josephson junction (LJJ) driven by a non-Gaussian Lévy noise current; (ii) a metastable quantum open system driven by an external periodical driving; and (iii) the electron spin relaxation process in n-type GaAs crystals driven by a fluctuating electric field. In the first system the LJJ phase evolution is described by the perturbed sine-Gordon equation. Two well known noise induced effects are found: the noise enhanced stability and resonant activation phenomena. We investigate the mean escape time as a function of the bias current frequency, nois…

Relaxationquantum dissipative systemelectron spin relaxationMetastability; Relaxation; Mesoscopic Systems; Josephson junction; sine-Gordon; soliton; Lévy noise; quantum dissipative system; Caldeira-Leggett; discrete variable representation; electron spin relaxation; Monte Carlo;Settore FIS/03 - Fisica Della MateriaLévy noiseMesoscopic SystemMetastabilitysine-Gordondiscrete variable representationJosephson junctionsolitonMonte CarloCaldeira-Leggett
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