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arXiv · 2203.16207

Entanglement swapping and quantum correlations via Elegant Joint Measurements

Cen-Xiao Huang·Xiao-Min Hu·Yu Guo·Chao Zhang·Bi-Heng Liu·Yun-Feng Huang·Chuan-Feng Li·Guang-Can Guo·Nicolas Gisin·Cyril Branciard·Armin Tavakoli
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Abstract

We use hyper-entanglement to experimentally realize deterministic entanglement swapping based on quantum Elegant Joint Measurements. These are joint projections of two qubits onto highly symmetric, iso-entangled, bases. We report measurement fidelities no smaller than $97.4\%$. We showcase the applications of these measurements by using the entanglement swapping procedure to demonstrate quantum correlations in the form of proof-of-principle violations of both bilocal Bell inequalities and more stringent correlation criteria corresponding to full network nonlocality. Our results are a foray into entangled measurements and nonlocality beyond the paradigmatic Bell state measurement and they show the relevance of more general measurements in entanglement swapping scenarios.

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Cen-Xiao Huang, Xiao-Min Hu, Yu Guo, Chao Zhang, Bi-Heng Liu, Yun-Feng Huang, Chuan-Feng Li, Guang-Can Guo, Nicolas Gisin, Cyril Branciard, Armin Tavakoli. 2022-03-30. Entanglement swapping and quantum correlations via Elegant Joint Measurements. https://doi.org/10.1103/physrevlett.129.030502

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