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arXiv · 2101.08541

Experimental demonstration of memory-enhanced scaling for entanglement connection of quantum repeater segments

Yunfei Pu·Sheng Zhang·Yukai Wu·Nan Jiang·Wei Chang·Chang Li·Luming Duan
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Abstract

The quantum repeater protocol is a promising approach to implement long-distance quantum communication and large-scale quantum networks. A key idea of the quantum repeater protocol is to use long-lived quantum memories to achieve efficient entanglement connection between different repeater segments with a polynomial scaling. Here we report an experiment which realizes efficient connection of two quantum repeater segments via on-demand entanglement swapping by the use of two atomic quantum memories with storage time of tens of milliseconds. With the memory enhancement, scaling-changing acceleration is demonstrated in the rate for a successful entanglement connection. The experimental realization of entanglement connection of two quantum repeater segments with an efficient memory-enhanced scaling demonstrates a key advantage of the quantum repeater protocol, which makes a cornerstone towards future large-scale quantum networks.

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Yunfei Pu, Sheng Zhang, Yukai Wu, Nan Jiang, Wei Chang, Chang Li, Luming Duan. 2021-01-21. Experimental demonstration of memory-enhanced scaling for entanglement connection of quantum repeater segments. https://doi.org/10.1038/s41566-021-00764-4

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