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arXiv · 2105.10298

Robust Self-Testing of Multiparticle Entanglement

Dian Wu·Qi Zhao·Xue-Mei Gu·Han-Sen Zhong·You Zhou·Li-Chao Peng·Jian Qin·Yi-Han Luo·Kai Chen·Li Li·Nai-Le Liu·Chao-Yang Lu·Jian-Wei Pan
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Abstract

Quantum self-testing is a device-independent way to certify quantum states and measurements using only the input-output statistics, with minimal assumptions about the quantum devices. Because of the high demand on tolerable noise, however, experimental self-testing was limited to two-photon systems. Here, we demonstrate the first robust self-testing for multi-photon genuinely entangled quantum states. We prepare two examples of four-photon graph states, the Greenberger-Horne-Zeilinger (GHZ) states with a fidelity of 0.957(2) and the linear cluster states with a fidelity of 0.945(2). Based on the observed input-output statistics, we certify the genuine four-photon entanglement and further estimate their qualities with respect to realistic noise in a device-independent manner.

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Dian Wu, Qi Zhao, Xue-Mei Gu, Han-Sen Zhong, You Zhou, Li-Chao Peng, Jian Qin, Yi-Han Luo, Kai Chen, Li Li, Nai-Le Liu, Chao-Yang Lu, Jian-Wei Pan. 2021-05-21. Robust Self-Testing of Multiparticle Entanglement. https://doi.org/10.1103/physrevlett.127.230503

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