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Optimal entanglement criterion for mixed quantum states

Heinz-Peter Breuer
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Abstract

We develop a strong and computationally simple entanglement criterion. The criterion is based on an elementary positive map Phi which operates on state spaces with even dimension N >= 4. It is shown that Phi detects many entangled states with positive partial transposition (PPT) and that it leads to a class of optimal entanglement witnesses. This implies that there are no other witnesses which can detect more entangled PPT states. The map Phi yields a systematic method for the explicit construction of high-dimensional manifolds of bound entangled states.

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Heinz-Peter Breuer. 2006-08-22. Optimal entanglement criterion for mixed quantum states. https://doi.org/10.1103/physrevlett.97.080501

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