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arXiv · 1006.3059

Constructing optimal entanglement witnesses. II

Dariusz Chruscinski·Justyna Pytel
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Abstract

We provide a class of optimal nondecomposable entanglement witnesses for 4N x 4N composite quantum systems or, equivalently, a new construction of nondecomposable positive maps in the algebra of 4N x 4N complex matrices. This construction provides natural generalization of the Robertson map. It is shown that their structural physical approximations give rise to entanglement breaking channels.

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Dariusz Chruscinski, Justyna Pytel. 2010-06-15. Constructing optimal entanglement witnesses. II. https://doi.org/10.1103/physreva.82.052310

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