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arXiv · 1205.3119

Determining lower bounds on a measure of multipartite entanglement from few local observables

Jun-Yi Wu·Hermann Kampermann·Dagmar Bruß·Claude Klöckl·Marcus Huber
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Abstract

We introduce a method to lower bound an entropy-based measure of genuine multipartite entanglement via nonlinear entanglement witnesses. We show that some of these bounds are tight and explicitly work out their connection to a framework of nonlinear witnesses that were published recently. Furthermore we provide a detailed analysis of these lower bounds in the context of other possible bounds and measures. In exemplary cases we show that only a few local measurements are necessary to determine these lower bounds.

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Jun-Yi Wu, Hermann Kampermann, Dagmar Bruß, Claude Klöckl, Marcus Huber. 2012-08-20. Determining lower bounds on a measure of multipartite entanglement from few local observables. https://doi.org/10.1103/physreva.86.022319

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