Quantum computational advantage using photons

Han-Sen Zhong; Hui Wang; Yu-Hao Deng; Ming-Cheng Chen; Li-Chao Peng; Yi-Han Luo; Jian Qin; Dian Wu; Xing Ding; Yi Hu; Peng Hu; Xiao-Yan Yang; Wei-Jun Zhang; Hao Li; Yuxuan Li; Xiao Jiang; Lin Gan; Guangwen Yang; Lixing You; Zhen Wang; Li Li; Nai-Le Liu; Chao-Yang Lu; Jian-Wei Pan

doi:10.1126/science.abe8770

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arXiv · 2012.01625

Quantum computational advantage using photons

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Abstract

Gaussian boson sampling exploits squeezed states to provide a highly efficient way to demonstrate quantum computational advantage. We perform experiments with 50 input single-mode squeezed states with high indistinguishability and squeezing parameters, which are fed into a 100-mode ultralow-loss interferometer with full connectivity and random transformation, and sampled using 100 high-efficiency single-photon detectors. The whole optical set-up is phase-locked to maintain a high coherence between the superposition of all photon number states. We observe up to 76 output photon-clicks, which yield an output state space dimension of $10^{30}$ and a sampling rate that is $10^{14}$ faster than using the state-of-the-art simulation strategy and supercomputers. The obtained samples are validated against various hypotheses including using thermal states, distinguishable photons, and uniform distribution.

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Han-Sen Zhong, Hui Wang, Yu-Hao Deng, Ming-Cheng Chen, Li-Chao Peng, Yi-Han Luo, Jian Qin, Dian Wu, Xing Ding, Yi Hu, Peng Hu, Xiao-Yan Yang, Wei-Jun Zhang, Hao Li, Yuxuan Li, Xiao Jiang, Lin Gan, Guangwen Yang, Lixing You, Zhen Wang, Li Li, Nai-Le Liu, Chao-Yang Lu, Jian-Wei Pan. 2020-12-03. Quantum computational advantage using photons. https://doi.org/10.1126/science.abe8770

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