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arXiv · 1606.02173

Non-markovian mesoscopic dissipative dynamics of open quantum spin chains

Fabio Benatti·Federico Carollo·Roberto Floreanini·Heide Narnhofer
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Abstract

We study the dissipative dynamics of $N$ quantum spins with Lindblad generator consisting of operators scaling as fluctuations, namely with the inverse square-root of $N$. In the large $N$ limit, the microscopic dissipative time-evolution converges to a non-Markovian unitary dynamics on strictly local operators, while at the mesoscopic level of fluctuations it gives rise to a dissipative non-Markovian dynamics. The mesoscopic time-evolution is Gaussian and exhibits either a stable or an unstable asymptotic character; furthermore, the mesoscopic dynamics builds correlations among fluctuations that survive in time even when the original microscopic dynamics is unable to correlate local observables.

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Fabio Benatti, Federico Carollo, Roberto Floreanini, Heide Narnhofer. 2016-06-07. Non-markovian mesoscopic dissipative dynamics of open quantum spin chains. https://doi.org/10.1016/j.physleta.2015.10.062

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