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Three-party entanglement from positronium

A. Acin·J. I. Latorre·P. Pascual
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Abstract

The decay of ortho-positronium into three photons produces a physical realization of a pure state with three-party entanglement. Its quantum correlations are analyzed using recent results on quantum information theory, looking for the final state which has the maximal amount of GHZ-like correlations. This state allows for a statistical dismissal of local realism stronger than the one obtained using any entangled state of two spin one-half particles.

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A. Acin, J. I. Latorre, P. Pascual. 2000-07-20. Three-party entanglement from positronium. https://doi.org/10.1103/physreva.63.042107

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