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arXiv · 1106.2018

Collective Uncertainty Entanglement Test

Łukasz Rudnicki·Paweł Horodecki·Karol Życzkowski
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Abstract

For a given pure state of a composite quantum system we analyze the product of its projections onto a set of locally orthogonal separable pure states. We derive a bound for this product analogous to the entropic uncertainty relations. For bipartite systems the bound is saturated for maximally entangled states and it allows us to construct a family of entanglement measures, we shall call collectibility. As these quantities are experimentally accessible, the approach advocated contributes to the task of experimental quantification of quantum entanglement, while for a three-qubit system it is capable to identify the genuine three-party entanglement.

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Łukasz Rudnicki, Paweł Horodecki, Karol Życzkowski. 2011-06-10. Collective Uncertainty Entanglement Test. https://doi.org/10.1103/physrevlett.107.150502

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