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arXiv · 0908.3467

Estimating multipartite entanglement measures

A. Osterloh·P. Hyllus
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Abstract

We investigate the lower bound obtained from experimental data of a quantum state $\rho$, as proposed independently by G\"uhne et al. and Eisert et al. for mixed states of three qubits. The measure we consider is the convex-roof extended three-tangle. Our findings highlight an intimate relation to lower bounds obtained recently from so-called characteristic curves of a given entanglement measure. We apply the bounds to estimate the three-tangle present in recently performed experiments aimed at producing a three-qubit GHZ state. A non-vanishing lower bound is obtained if the GHZ-fidelity of the produced states is larger than 3/4.

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A. Osterloh, P. Hyllus. 2009-08-24. Estimating multipartite entanglement measures. https://doi.org/10.1103/physreva.81.022307

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