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arXiv · 1212.6378

Separability of qubit-qudit quantum states with strong positive partial transposes

Kil-Chan Ha
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Abstract

We show that all $2\otimes 4$ states with strong positive partial transposes (SPPT) are separable. We also construct a family of $2\otimes 5$ entangled SPPT states, so the conjecture on the separability of SPPT states are completely settled. In addition, we clarify the relation between the set of all $2\otimes d$ separable states and the set of all $2\otimes d$ SPPT states for the case of $d=3,4$.

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Kil-Chan Ha. 2012-12-27. Separability of qubit-qudit quantum states with strong positive partial transposes. https://doi.org/10.1103/physreva.87.024301

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