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arXiv · 1809.04289

General Hardy-Type Paradox Based on Bell inequality and its Experimental Test

Mu Yang·Hui-Xian Meng·Jie Zhou·Zhen-Peng Xu·Ya Xiao·Kai Sun·Jing-Ling Chen·Jin-Shi Xu·Chuan-Feng Li·Guang-Can Guo
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Abstract

Local realistic models cannot completely describe all predictions of quantum mechanics. This is known as Bell's theorem that can be revealed either by violations of Bell inequality, or all-versus-nothing proof of nonlocality. Hardy's paradox is an important all-versus-nothing proof and is considered as "the simplest form of Bell's theorem". In this work, we theoretically build the general framework of Hardy-type paradox based on Bell inequality. Previous Hardy's paradoxes have been found to be special cases within the framework. Stronger Hardy-type paradox has been found even for the two-qubit two-setting case, and the corresponding successful probability is about four times larger than the original one, thus providing a more friendly test for experiment. We also find that GHZ paradox can be viewed as a perfect Hardy-type paradox. Meanwhile, we experimentally test the stronger Hardy-type paradoxes in a two-qubit system. Within the experimental errors, the experimental results coincide with the theoretical predictions.

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Mu Yang, Hui-Xian Meng, Jie Zhou, Zhen-Peng Xu, Ya Xiao, Kai Sun, Jing-Ling Chen, Jin-Shi Xu, Chuan-Feng Li, Guang-Can Guo. 2018-09-12. General Hardy-Type Paradox Based on Bell inequality and its Experimental Test. https://doi.org/10.1103/physreva.99.032103

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