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arXiv · 1206.0504

Optimal indecomposable witnesses without extremality as well as spanning property

Kil-Chan Ha·Hoseog Yu
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Abstract

One of the interesting problems on optimal indecomposable entanglement witnesses is whether there exists an optimal indecomposable witness which neither has the spanning property nor is associated with extremal positive linear map. Here, we answer this question negatively by examining the extremality of the positive linear maps constructed by Qi and Hou [J. Phys. A {\bf 44}, 215305 (2100)].

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Kil-Chan Ha, Hoseog Yu. 2012-06-04. Optimal indecomposable witnesses without extremality as well as spanning property. https://doi.org/10.1088/1751-8113/45/39/395307

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