Hua-Liang Liu, Hao Su, Si-Qiu Gong, Yi-Chao Gu, Hao-Yang Tang, Meng-Hao Jia, Qian Wei, Yukun Song, Dongzhou Wang, Mingyang Zheng, Faxi Chen, Libo Li, Siyu Ren, Xuezhi Zhu, Meihong Wang, Yaojian Chen, Yanfei Liu, Longsheng Song, Pengyu Yang, Junshi Chen, et al (17) (Aug 13 2025).

Abstract: The creation of large-scale, high-fidelity quantum computers is not only a fundamental scientific endeavour in itself, but also provides increasingly robust proofs of quantum computational advantage (QCA) in the pres- ence of unavoidable noise and the dynamic competition with classical algorithm improvements. To overcome the biggest challenge of photon-based QCA experiments, photon loss, we report new Gaussian boson sampling (GBS) experiments with 1024 high-efficiency squeezed states injected into a hybrid spatial-temporal encoded, 8176-mode, programmable photonic quantum processor, Jiuzhang 4.0, which produces up to 3050 photon de- tection events. Our experimental results outperform all classical spoofing algorithms, particularly the matrix product state (MPS) method, which was recently proposed to utilise photon loss to reduce the classical simula- tion complexity of the GBS. Using the state-of-the-art MPS algorithm on the most powerful supercomputer EI Capitan, it would take > 1042 years to construct the required tensor network for simulation, while our Jiuzhang 4.0 quantum computer takes 25.6 \mus to produce a sample. This work establishes a new frontier of QCA and paves the way to fault-tolerant photonic quantum computing hardware.

Arxiv: https://arxiv.org/abs/2508.09092