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arXiv · 1908.05351

Experimental quantum repeater without quantum memory

Zheng-Da Li·Rui Zhang·Xu-Fei Yin·Li-Zheng Liu·Yi Hu·Yu-Qiang Fang·Yue-Yang Fei·Xiao Jiang·Jun Zhang·Li Li·Nai-Le Liu·Feihu Xu·Yu-Ao Chen·Jian-Wei Pan
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Abstract

Quantum repeaters -- important components of a scalable quantum internet -- enable the entanglement to be distributed over long distances. The standard paradigm for a quantum repeater relies on a necessary demanding requirement of quantum memory. Despite significant progress, the limited performance of quantum memory makes practical quantum repeaters still a great challenge. Remarkably, a proposed all-photonic quantum repeater avoids the need for quantum memory by harnessing the graph states in the repeater nodes. Here we perform an experimental demonstration of an all-photonic quantum repeater using linear optics. By manipulating a 12-photon interferometer, we implement a 2-by-2 parallel all-photonic quantum repeater, and observe an 89% enhancement of entanglement-generation rate over the standard parallel entanglement swapping. These results open a new way towards designing repeaters with efficient single-photon sources and photonic graph states, and suggest that the all-photonic scheme represents an alternative path -- parallel to that of matter-memory-based schemes -- towards realizing practical quantum repeaters.

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Zheng-Da Li, Rui Zhang, Xu-Fei Yin, Li-Zheng Liu, Yi Hu, Yu-Qiang Fang, Yue-Yang Fei, Xiao Jiang, Jun Zhang, Li Li, Nai-Le Liu, Feihu Xu, Yu-Ao Chen, Jian-Wei Pan. 2019-08-14. Experimental quantum repeater without quantum memory. https://doi.org/10.1038/s41566-019-0468-5

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