Search results for "Metastability"

showing 2 items of 262 documents

NONEQUILIBRIUM PHENOMENA AND METASTABILITY IN MESOSCOPIC AND QUANTUM SYSTEMS

2020

Here we summarize some relevant results related to nonequilibrium phenomena in mesoscopic and quantum systems. A common phenomenon in the dynamics of out-of-equilibrium systems is the metastability, and the problem of the lifetime of metastable states involves fundamental aspects of nonequilibrium statistical mechanics. Metastability (see Fig. 1) is a signature of a first order phase transition, often characterized by a long-living metastable state. In particular, the stability of a metastable state can be enhanced by Gaussian and non-Gaussian noise sources. This counterintuitive effect has been found in different physical areas, ranging from spintronics, aggregation kinetics of Brownian pa…

metastabilitySettore FIS/02 - Fisica Teorica Modelli E Metodi Matematicidynamics of out-of-equilibrium systemmesoscopic systemquantum systemSettore FIS/03 - Fisica Della MateriaSettore FIS/07 - Fisica Applicata(Beni Culturali Ambientali Biol.e Medicin)
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Enhancing Metastability by Dissipation and Driving in an Asymmetric Bistable Quantum System.

2018

The stabilizing effect of quantum fluctuations on the escape process and the relaxation dynamics from a quantum metastable state are investigated. Specifically, the quantum dynamics of a multilevel bistable system coupled to a bosonic Ohmic thermal bath in strong dissipation regime is analyzed. The study is performed by a non-perturbative method based on the real-time path integral approach of the Feynman-Vernon influence functional. We consider a strongly asymmetric double well potential with and without a monochromatic external driving, and with an out-of-equilibrium initial condition. In the absence of driving we observe a nonmonotonic behavior of the escape time from the metastable regi…

quantum statistical methodsQuantum dynamicsquantum Zeno dynamicsGeneral Physics and AstronomyDouble-well potentiallcsh:AstrophysicsReview01 natural sciencesSettore FIS/03 - Fisica Della Materia010305 fluids & plasmasPhysics and Astronomy (all)functional analytical methodstunnelingMetastability0103 physical scienceslcsh:QB460-466Quantum system010306 general physicslcsh:ScienceQuantum statistical methodQuantum fluctuationQuantum tunnellingPhysicsCondensed matter physicsQuantum noiseFunctional analytical methodQuantum Zeno dynamiclcsh:QC1-999noise enhanced stabilitymetastable potentialdiscrete variable representationOpen systemopen systemsRelaxation (physics)lcsh:Qresonant activationCaldeira-Leggett modellcsh:Physicsquantum systems with finite Hilbert spaceEntropy (Basel, Switzerland)
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