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arXiv · 1708.06208

Quantum non-Markovianity and localization

David Davalos·Carlos Pineda
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Abstract

We study the behavior of non-Markovianity with respect to the localization of the initial environmental state. The "amount" of non-Markovianity is measured using divisibility and distinguishability as indicators, employing several schemes to construct the measures. The system used is a qubit coupled to an environment modeled by an Ising spin chain kicked by ultra-short pulses of a magnetic field. In the integrable regime, non-Markovianity and localization do not have a simple relation, but as the chaotic regime is approached, simple relations emerge, which we explore in detail. We also study the non-Markovianity measures in the space of the parameters of the spin coherent states and point out that the pattern that appears is robust under the choice of the interaction Hamiltonian but does not have a KAM-like phase-space structure.

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David Davalos, Carlos Pineda. 2017-08-21. Quantum non-Markovianity and localization. https://doi.org/10.1103/physreva.96.062127

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