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Experimental Violation of Bell Inequality beyond Cirel'son's Bound

Yu-Ao Chen·Tao Yang·An-Ning Zhang·Zhi Zhao·Adan Cabello·Jian-Wei Pan
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Abstract

The correlations between two qubits belonging to a three-qubit system can violate the Clauser-Horne-Shimony-Holt-Bell inequality beyond Cirel'son's bound [A. Cabello, Phys. Rev. Lett. 88, 060403 (2002)]. We experimentally demonstrate such a violation by 7 standard deviations by using a three-photon polarization-entangled Greenberger-Horne-Zeilinger state produced by Type-II spontaneous parametric down-conversion. In addition, using part of our results, we obtain a violation of the Mermin inequality by 39 standard deviations.

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Yu-Ao Chen, Tao Yang, An-Ning Zhang, Zhi Zhao, Adan Cabello, Jian-Wei Pan. 2006-07-27. Experimental Violation of Bell Inequality beyond Cirel'son's Bound. https://doi.org/10.1103/physrevlett.97.170408

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