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Estimating entanglement measures in experiments

O. Gühne·M. Reimpell·R. F. Werner
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Abstract

We present a method to estimate entanglement measures in experiments. We show how a lower bound on a generic entanglement measure can be derived from the measured expectation values of any finite collection of entanglement witnesses. Hence witness measurements are given a quantitative meaning without the need of further experimental data. We apply our results to a recent multi-photon experiment [M. Bourennane et al., Phys. Rev. Lett. 92, 087902 (2004)], giving bounds on the entanglement of formation and the geometric measure of entanglement in this experiment.

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O. Gühne, M. Reimpell, R. F. Werner. 2007-03-12. Estimating entanglement measures in experiments. https://doi.org/10.1103/physrevlett.98.110502

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