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arXiv · 1802.00806

Unified approach to geometric and positive-map-based non-linear entanglement identifiers

Marcin Markiewicz·Adrian Kolodziejski·Zbigniew Puchala·Adam Rutkowski·Tomasz Tylec·Wieslaw Laskowski
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Abstract

Detecting quantumness of correlations (especially entanglement) is a very hard task even in the simplest case i.e. two-partite quantum systems. Here we provide an analysis whether there exists a relation between two most popular types of entanglement identifiers: the first one based on positive maps and not directly applicable in laboratory and the second one --- geometric entanglement identifier which is based on specific Hermiticity-preserving maps. We show a profound relation between those two types of entanglement criteria. Hereunder we have proposed a general framework of nonlinear functional entanglement identifiers which allows us to construct new experimentally friendly entanglement criteria.

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Marcin Markiewicz, Adrian Kolodziejski, Zbigniew Puchala, Adam Rutkowski, Tomasz Tylec, Wieslaw Laskowski. 2018-02-02. Unified approach to geometric and positive-map-based non-linear entanglement identifiers. https://doi.org/10.1103/physreva.97.042339

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