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arXiv · 2101.09463

Non-Markovian effects in the spin-boson model at zero temperature

Sebastian Wenderoth·Heinz-Peter Breuer·Michael Thoss
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Abstract

We investigate memory effects in the spin-boson model using a recently proposed measure for non-Markovian behavior based on the information exchange between an open system and its environment. Employing the numerical exact multilayer multiconfguration time-dependent Hartree approach, we simulate the dynamics of the spin-boson model at zero temperature for a broad range of parameters. For a fast bath, i.e. in the scaling limit, we find non-Markovian dynamics for a coherently decaying spin at weak system-bath coupling, whereas memory effects are absent for stronger coupling in the regimes of incoherent decay and localization. If the time scales of system and bath are comparable, a complex, non-monotonic dependence of non-Markovianity on the system-bath coupling strength is observed.

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Sebastian Wenderoth, Heinz-Peter Breuer, Michael Thoss. 2021-01-23. Non-Markovian effects in the spin-boson model at zero temperature. https://doi.org/10.1103/physreva.104.012213

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