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arXiv · 1709.05492

Non-Markovian Dynamics of Macroscopic Quantum Systems in Interaction with Non-Equilibrium Environments

Nasim Shahmansoori·Farhad Taher Ghahramani·Afshin Shafiee
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Abstract

We study the dynamics of a macroscopic superconducting qubit coupled to two independent non-stationary reservoirs by using time-dependent perturbation theory. We show that an equilibrium environment surpasses the coherent evolution of the macroscopic qubit completely. When the qubit couples to two different reservoirs, exemplifying a non-equilibrium environment, the short-time dynamics is affected by the interference between two reservoirs, implying the non-additivity of effects of two reservoirs. The non-additivity can be traced back to a non-Markovian effect, even though two reservoirs are independently assumed to be Markovian. Explicitly, the non-equilibrium environment intensifies both coherent and incoherent parts of the evolution. Therefore, the macroscopic qubit would evolve more coherently but at the price of a shorter decoherence time.

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Nasim Shahmansoori, Farhad Taher Ghahramani, Afshin Shafiee. 2017-09-16. Non-Markovian Dynamics of Macroscopic Quantum Systems in Interaction with Non-Equilibrium Environments. https://arxiv.org/abs/1709.05492

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