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arXiv · 1510.05624

Quantum dissipative dynamics of a bistable system in the sub-Ohmic to super-Ohmic regime

Luca Magazzù·Angelo Carollo·Bernardo Spagnolo·Davide Valenti
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Abstract

We investigate the quantum dynamics of a multilevel bistable system coupled to a bosonic heat bath beyond the perturbative regime. We consider different spectral densities of the bath, in the transition from sub-Ohmic to super-Ohmic dissipation, and different cutoff frequencies. The study is carried out by using the real-time path integral approach of the Feynman-Vernon influence functional. We find that, in the crossover dynamical regime characterized by damped \emph{intrawell} oscillations and incoherent tunneling, the short time behavior and the time scales of the relaxation starting from a nonequilibrium initial condition depend nontrivially on the spectral properties of the heat bath.

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Luca Magazzù, Angelo Carollo, Bernardo Spagnolo, Davide Valenti. 2015-10-19. Quantum dissipative dynamics of a bistable system in the sub-Ohmic to super-Ohmic regime. https://doi.org/10.1088/1742-5468%2F2016%2F05%2F054016

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