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arXiv · 1712.06557

Observation of stronger-than-binary correlations with entangled photonic qutrits

Xiao-Min Hu·Bi-Heng Liu·Yu Guo·Guo-Yong Xiang·Yun-Feng Huang·Chuan-Feng Li·Guang-Can Guo·Matthias Kleinmann·Tamás Vértesi·Adán Cabello
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Abstract

We present the first experimental confirmation of the quantum-mechanical prediction of stronger-than-binary correlations. These are correlations that cannot be explained under the assumption that the occurrence of a particular outcome of an $n \ge 3$-outcome measurement is due to a two-step process in which, in the first step, some classical mechanism precludes $n-2$ of the outcomes and, in the second step, a binary measurement generates the outcome. Our experiment uses pairs of photonic qutrits distributed between two laboratories, where randomly chosen three-outcome measurements are performed. We report a violation by {9.3} standard deviations of the optimal inequality for nonsignaling binary correlations.

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Xiao-Min Hu, Bi-Heng Liu, Yu Guo, Guo-Yong Xiang, Yun-Feng Huang, Chuan-Feng Li, Guang-Can Guo, Matthias Kleinmann, Tamás Vértesi, Adán Cabello. 2017-12-18. Observation of stronger-than-binary correlations with entangled photonic qutrits. https://doi.org/10.1103/physrevlett.120.180402

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