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arXiv · 1904.07650

Bounds on bipartite entanglement from fixed marginals

Giuseppe Baio·Dariusz Chruscinski·Pawel Horodecki·Antonino Messina·Gniewomir Sarbicki
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Abstract

We discuss the problem of characterizing upper bounds on entanglement in a bipartite quantum system when only the reduced density matrices (marginals) are known. In particular, starting from the known two-qubit case, we propose a family of candidates for maximally entangled mixed states with respect to fixed marginals for two qudits. Interestingly, it turns out such states are always quasidistillable. Moreover, they are extremal in the convex set of two qudit states with fixed marginals. Our observations are supported by numerical analysis.

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Giuseppe Baio, Dariusz Chruscinski, Pawel Horodecki, Antonino Messina, Gniewomir Sarbicki. 2019-04-16. Bounds on bipartite entanglement from fixed marginals. https://doi.org/10.1103/physreva.99.062312

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