Search results for "Caldeira-Leggett model"

showing 3 items of 3 documents

Quantum Relaxation Time in Asymmetric Bistable Potential

2010

Quantum tunneling effect occurs often in condensed matter physics, examples are JJs, heteronanostructures, etc.. The tunneling effect plays an important role in the nonlinear relaxation time from a metastable state in an open quantum system, interacting with a thermal bath. Symmetrical and asymmetric bistable systems are good quantum model systems for analysis of the "superconducting quantum bits" and decoherence phenomena. To obtain very long coherence times in the presence of interaction between the qubit and the noisy environment is one of the greatest challenges of physics. The inf1uence of the environment in quantum tunneling has been in the focus of intense research over the last year…

Discrete variable representationNoise enhanced stabilityCaldeira-Leggett modelSettore FIS/03 - Fisica Della MateriaBistable potential
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Dynamics of a Quantum Particle in Asymmetric Bistable Potential with Environmental Noise

2011

In this work we analyze the dynamics of a quantum particle subject to an asymmetric bistable potential and interacting with a thermal reservoir. We obtain the time evolution of the population distributions in both energy and position eigenstates of the particle, for different values of the coupling strength with the thermal bath. The calculation is carried out using the Feynman-Vernon functional under the discrete variable representation.

PhysicsWork (thermodynamics)Physics and Astronomy (miscellaneous)BistabilityThermal reservoirTime evolutionBistable potential; Noise Enhanced Stability; Discrete Variable Representation; Caldeira-Leggett modelNoise Enhanced StabilitySettore FIS/03 - Fisica Della MateriaBistable potentialDVRPosition (vector)Quantum mechanicsThermalNESParticleEigenvalues and eigenvectorsDiscrete Variable RepresentationCaldeira-Leggett model
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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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