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Investigating three qubit entanglement with local measurements

Otfried Gühne·Philipp Hyllus
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Abstract

In this paper we describe how three qubit entanglement can be analyzed with local measurements. For this purpose we decompose entanglement witnesses into operators which can be measured locally. Our decompositions are optimized in the number of measurement settings needed for the measurement of one witness. Our method allows to detect true threepartite entanglement and especially GHZ-states with only four measurement settings.

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Otfried Gühne, Philipp Hyllus. 2003-01-29. Investigating three qubit entanglement with local measurements. https://doi.org/10.1023/a%3A1025422606845

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