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arXiv · 2203.07979

Loss-tolerant all-photonic quantum repeater with generalized Shor code

Rui Zhang·Li-Zheng Liu·Zheng-Da Li·Yue-Yang Fei·Xu-Fei Yin·Li Li·Nai-Le Liu·Yingqiu Mao·Yu-Ao Chen·Jian-Wei Pan
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Abstract

The all-photonic quantum repeater (APQR) is a promising repeater scheme to realize long-distance quantum communication. For a practical APQR, an indispensable requirement is the robustness of the repeater graph state (RGS) against photon loss. We propose a new loss-tolerant scheme by applying the generalized Shor code to RGS, which can be experimentally demonstrated with current technology. Experimentally, we first prepare and verify the nine-qubit Shor code. Then, by applying the generalized Shor code to APQR and preparing a simplified encoded RGS with the structure of $1\times2$ based on the Shor code state, the effectiveness of our loss-tolerant scheme and the loss tolerance of the encoded RGS are respectively verified. Our results make an essential step toward a practical APQR and enrich the research of quantum error correction code.

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Rui Zhang, Li-Zheng Liu, Zheng-Da Li, Yue-Yang Fei, Xu-Fei Yin, Li Li, Nai-Le Liu, Yingqiu Mao, Yu-Ao Chen, Jian-Wei Pan. 2022-03-15. Loss-tolerant all-photonic quantum repeater with generalized Shor code. https://doi.org/10.1364/optica.439170

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