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Experimental Entangled Entanglement

Philip Walther·Kevin J. Resch·Caslav Brukner·Anton Zeilinger
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Abstract

All previous tests of local realism have studied correlations between single-particle measurements. In the present experiment, we have performed a Bell experiment on three particles in which one of the measurements corresponds to a projection onto a maximally-entangled state. We show theoretically and experimentally, that correlations between these entangled measurements and single-particle measurements are too strong for any local-realistic theory and are experimentally exploited to violate a CHSH-Bell inequality by more than 5 standard deviations. We refer to this possibility as "entangled entanglement".

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Philip Walther, Kevin J. Resch, Caslav Brukner, Anton Zeilinger. 2006-07-25. Experimental Entangled Entanglement. https://doi.org/10.1103/physrevlett.97.020501

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