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arXiv · 2208.07794

Exploring the boundary of quantum correlations with a time-domain optical processor

Zheng-Hao Liu·Yu Meng·Yu-Ze Wu·Ze-Yan Hao·Zhen-Peng Xu·Cheng-Jun Ai·Hai Wei·Kai Wen·Jing-Ling Chen·Jie Ma·Jin-Shi Xu·Chuan-Feng Li·Guang-Can Guo
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Abstract

Contextuality is a hallmark feature of the quantum theory that captures its incompatibility with any noncontextual hidden-variable model. The Greenberger--Horne--Zeilinger (GHZ)-type paradoxes are proofs of contextuality that reveal this incompatibility with deterministic logical arguments. However, the GHZ-type paradox whose events can be included in the fewest contexts and which brings the strongest nonclassicality remains elusive. Here, we derive a GHZ-type paradox with a context-cover number of three and show this number saturates the lower bound posed by quantum theory. We demonstrate the paradox with a time-domain fiber optical platform and recover the quantum prediction in a 37-dimensional setup based on high-speed modulation, convolution, and homodyne detection of time-multiplexed pulsed coherent light. By proposing and studying a strong form of contextuality in high-dimensional Hilbert space, our results pave the way for the exploration of exotic quantum correlations with time-multiplexed optical systems.

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Zheng-Hao Liu, Yu Meng, Yu-Ze Wu, Ze-Yan Hao, Zhen-Peng Xu, Cheng-Jun Ai, Hai Wei, Kai Wen, Jing-Ling Chen, Jie Ma, Jin-Shi Xu, Chuan-Feng Li, Guang-Can Guo. 2022-08-16. Exploring the boundary of quantum correlations with a time-domain optical processor. https://doi.org/10.1126/sciadv.abd8080

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