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arXiv · 1307.5768

Exact dynamics and thermalization of an open bosonic quantum system in presence of a quantum phase transition induced by the environment

A. Rancon·J. Bonart
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Abstract

We derive the exact out-of-equilibrium Wigner function of a bosonic mode linearly coupled to a bosonic bath of arbitrary spectral density. Our solution does not rely on any master equation approach and it therefore also correctly describes a bosonic mode which is initially entangled with its environment. It has been recently suggested that non-Markovian quantum effects lead to dissi- pationless dynamics in the case of a strong coupling to a bath whose spectral density has a support bounded from below. We show in this work that such a system undergoes a quantum phase transi- tion at some critical bath coupling strength. The apparent dissipationless dynamics then correspond to the relaxation towards the new ground-state.

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A. Rancon, J. Bonart. 2013-07-22. Exact dynamics and thermalization of an open bosonic quantum system in presence of a quantum phase transition induced by the environment. https://doi.org/10.1209/0295-5075%2F104%2F50010

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