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arXiv · 1412.7467

Dissipative dynamics in a quantum bistable system: Crossover from weak to strong damping

Luca Magazzù·Davide Valenti·Bernardo Spagnolo·Milena Grifoni
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Abstract

The dissipative dynamics of a quantum bistable system coupled to a Ohmic heat bath is investigated beyond the spin-boson approximation. Within the path-integral approach to quantum dissipation, we propose an approximation scheme which exploits the separation of time scales between intra- and interwell (tunneling) dynamics. The resulting generalized master equation for the populations in a space localized basis enables us to investigate a wide range of temperatures and system-environment coupling strengths. A phase diagram in the coupling-temperature space is provided to give a comprehensive account of the different dynamical regimes.

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Luca Magazzù, Davide Valenti, Bernardo Spagnolo, Milena Grifoni. 2017-09-17. Dissipative dynamics in a quantum bistable system: Crossover from weak to strong damping. https://doi.org/10.1103/physreve.92.032123

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