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arXiv · 1203.4540

Interaction-induced impeding of decoherence and anomalous diffusion

Dario Poletti·Jean-Sebastien Bernier·Antoine Georges·Corinna Kollath
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Abstract

We study how the interplay of dissipation and interactions affects the dynamics of a bosonic many-body quantum system. In the presence of both dissipation and strongly repulsive interactions, observables such as the coherence and the compressibility display three dynamical regimes: an initial exponential variation followed by a power-law regime and finally a slow exponential convergence to their asymptotic values corresponding to the infinite temperature state. These very long-time scales arise as dissipation forces the population of states disfavored by interactions. The long-time, strong coupling dynamics are understood by performing a mapping onto a classical diffusion process displaying non-Brownian behavior. While both dissipation and strong interactions tend to suppress coherence when acting separately, we find that strong interaction impedes the decoherence process generated by the dissipation.

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Dario Poletti, Jean-Sebastien Bernier, Antoine Georges, Corinna Kollath. 2012-03-20. Interaction-induced impeding of decoherence and anomalous diffusion. https://doi.org/10.1103/physrevlett.109.045302

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