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arXiv · 2412.18882

Boosted fusion gates above the percolation threshold for scalable graph-state generation

Yong-Peng Guo·Geng-Yan Zou·Xing Ding·Qi-Hang Zhang·Mo-Chi Xu·Run-Ze Liu·Jun-Yi Zhao·Zhen-Xuan Ge·Li-Chao Peng·Ke-Mi Xu·Yi-Yang Lou·Zhen Ning·Lin-Jun Wang·Hui Wang·Yong-Heng Huo·Yu-Ming He·Chao-Yang Lu·Jian-Wei Pan
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Abstract

Fusing small resource states into a larger, fully connected graph-state is essential for scalable photonic quantum computing. Theoretical analysis reveals that this can only be achieved when the success probability of the fusion gate surpasses a specific percolation threshold of 58.98% by using three-photon GHZ states as resource states. However, such an implementation of a fusion gate has never been experimentally realized before. Here, we successfully demonstrate a boosted fusion gate with a theoretical success probability of 75%, using deterministically generated auxiliary states. The success probability is experimentally measured to be 71.0(7)%. We further demonstrate the effectiveness of the boosted fusion gate by fusing two Bell states with a fidelity of 67(2)%. Our work paves a crucial path toward scalable linear optical quantum computing.

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Yong-Peng Guo, Geng-Yan Zou, Xing Ding, Qi-Hang Zhang, Mo-Chi Xu, Run-Ze Liu, Jun-Yi Zhao, Zhen-Xuan Ge, Li-Chao Peng, Ke-Mi Xu, Yi-Yang Lou, Zhen Ning, Lin-Jun Wang, Hui Wang, Yong-Heng Huo, Yu-Ming He, Chao-Yang Lu, Jian-Wei Pan. 2024-12-25. Boosted fusion gates above the percolation threshold for scalable graph-state generation. https://arxiv.org/abs/2412.18882

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