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arXiv · 0903.2213

Experimental entanglement of a six-photon symmetric Dicke state

Witlef Wieczorek·Roland Krischek·Nikolai Kiesel·Patrick Michelberger·Geza Toth·Harald Weinfurter
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Abstract

We report on the experimental observation and characterization of a six-photon entangled Dicke state. We obtain a fidelity as high as 0.654$\pm$0.024 and prove genuine six-photon entanglement by, amongst others, a two-setting witness yielding -0.422$\pm$0.148. This state has remarkable properties; e.g., it allows obtaining inequivalent entangled states of a lower qubit number via projective measurements, and it possesses a high entanglement persistency against qubit loss. We characterize the properties of the six-photon Dicke state experimentally by detecting and analyzing the entanglement of a variety of multipartite entangled states.

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Witlef Wieczorek, Roland Krischek, Nikolai Kiesel, Patrick Michelberger, Geza Toth, Harald Weinfurter. 2009-07-16. Experimental entanglement of a six-photon symmetric Dicke state. https://doi.org/10.1103/physrevlett.103.020504

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