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arXiv · 1903.07489

Information backflow as a resource for entanglement

Nicolás Mirkin·Pablo Poggi·Diego Wisniacki
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Abstract

The issue of whether non-Markovianity (NM) could be considered as a resource in quantum information has been a subject of intense debate for the last years. Recently, a simple mechanism was proposed in which one of the main features of NM, the backflow of information from the environment to the system, represents a fundamental and quantifiable resource for generating entanglement within an open quantum system coupled to a finite and small environment [N. Mirkin, P. Poggi and D. Wisniacki, Phys. Rev. A, 99(2), 020301(R)]. In this work, we extend the universality of this resource mechanism by studying a completely different and more general scheme where the system is coupled to an infinite structured reservoir. Under both setups, we show that the degree of NM univocally determines the optimal degree of entanglement reachable by controlling the open system. This result reveals the universality of a quantitative relation between entanglement and NM by using quantum optimal control.

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Nicolás Mirkin, Pablo Poggi, Diego Wisniacki. 2019-03-18. Information backflow as a resource for entanglement. https://doi.org/10.1103/physreva.99.062327

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