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arXiv:1211.5675 · Open Systems & Information Dynamics

Exposedness of Choi-Type Entanglement Witnesses and Applications to Lengths of Separable States

Kil-Chan Ha, Seung-Hyeok Kye

Published Nov 25, 2013• 13 citations
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Abstract

We present a large class of indecomposable exposed positive linear maps between 3 × 3 matrix algebras. We also construct two-qutrit separable states with lengths ten in the interior of their dual faces. With these examples, we show that the length of a separable state may decrease strictly when we mix it with another separable state.
DOI
10.1142/s1230161213500121

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