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arXiv · 1803.00175

Separability of multi-qubit states in terms of diagonal and anti-diagonal entries

Kil-Chan Ha·Kyung Hoon Han·Seung-Hyeok Kye
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Abstract

We give separability criteria for general multi-qubit states in terms of diagonal and anti-diagonal entries. We define two numbers which are obtained from diagonal and anti-diagonal entries, respectively, and compare them to get criteria. They give rise to characterizations of separability when all the entries are zero except for diagonal and anti-diagonal, like Greenberger-Horne-Zeilinger diagonal states. The criteria is strong enough to get nonzero volume of entanglement with positive partial transposes.

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Kil-Chan Ha, Kyung Hoon Han, Seung-Hyeok Kye. 2018-03-01. Separability of multi-qubit states in terms of diagonal and anti-diagonal entries. https://arxiv.org/abs/1803.00175

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