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arXiv · 1109.2300

A characterization of optimal entanglement witnesses

Xiaofei Qi·Jinchuan Hou
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Abstract

In this paper, we present a characterization of optimal entanglement witnesses in terms of positive maps and then provide a general method of checking optimality of entanglement witnesses. Applying it, we obtain new indecomposable optimal witnesses which have no spanning property. These also provide new examples which support a recent conjecture saying that the so-called structural physical approximations to optimal positive maps (optimal entanglement witnesses) give entanglement breaking maps (separable states).

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Xiaofei Qi, Jinchuan Hou. 2011-09-11. A characterization of optimal entanglement witnesses. https://doi.org/10.1103/physreva.85.022334

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