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arXiv · 1702.08427

Objectivity in non-Markovian spin-boson model

Aniello Lampo·Jan Tuziemski·Maciej Lewenstein·Jaroslaw K. Korbicz
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Abstract

Objectivity constitutes one of the main features of the macroscopic classical world. An important aspect of the quantum-to-classical transition issue is to explain how such a property arises from the microscopic quantum world. Recently, within the framework of open quantum systems, there has been proposed such a mechanism in terms of the, so-called, Spectrum Broadcast Structures. These are multipartite quantum states of the system of interest and a part of its environment, assumed to be under an observation. This approach requires a departure from the standard open quantum systems methods, as the environment cannot be completely neglected. In the present work we study the emergence of such a state-structures in one of the canonical models of the condensed matter theory: Spin-boson model, describing the dynamics of a two-level system coupled to an environment made up by a large number of harmonic oscillators. We pay much attention to the behavior of the model in the non-Markovian regime, in order to provide a testbed to analyze how the non-Markovian nature of the evolution affects the surfacing of a spectrum broadcast structure.

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Aniello Lampo, Jan Tuziemski, Maciej Lewenstein, Jaroslaw K. Korbicz. 2017-08-31. Objectivity in non-Markovian spin-boson model. https://doi.org/10.1103/physreva.96.012120

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