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arXiv · 2209.02808

Experimental test of high-dimensional quantum contextuality based on contextuality concentration

Zheng-Hao Liu·Hui-Xian Meng·Zhen-Peng Xu·Jie Zhou·Jing-Ling Chen·Jin-Shi Xu·Chuan-Feng Li·Guang-Can Guo·Adán Cabello
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Abstract

Contextuality is a distinctive feature of quantum theory and a fundamental resource for quantum computation. However, existing examples of contextuality in high-dimensional systems lack the necessary robustness required in experiments. Here we address this problem by identifying a family of noncontextuality inequalities whose maximum quantum violation grows with the dimension of the system. At first glance, this contextuality is the single-system version of multipartite Bell nonlocality taken to an extreme form. What is interesting is that the single-system version achieves the same degree of contextuality but uses a Hilbert space of lower dimension. That is, contextuality ``concentrates'' as the degree of contextuality per dimension increases. We show the practicality of this result by presenting an experimental test of contextuality in a seven-dimensional system. By simulating sequences of quantum ideal measurements with destructive measurements and repreparation in an all-optical setup, we report a violation of 68.7 standard deviations of the simplest case of the noncontextuality inequalities identified. Our results advance the investigation of high-dimensional contextuality, its connection to the Clifford algebra, and its role in quantum computation.

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Zheng-Hao Liu, Hui-Xian Meng, Zhen-Peng Xu, Jie Zhou, Jing-Ling Chen, Jin-Shi Xu, Chuan-Feng Li, Guang-Can Guo, Adán Cabello. 2022-09-06. Experimental test of high-dimensional quantum contextuality based on contextuality concentration. https://doi.org/10.1103/physrevlett.130.240202

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