Quantum computational advantage using photons

Quantum computers promise to perform certain tasks that are believed to be intractable to classical computers. Boson sampling is such a task and is considered a strong candidate to demonstrate the quantum computational advantage. We performed Gaussian boson sampling by sending 50 indistinguishable single-mode squeezed states into a 100-mode ultralow-loss interferometer with full connectivity and random matrix-the whole optical setup is phase-locked-and sampling the output using 100 high-efficiency single-photon detectors. The obtained samples were validated against plausible hypotheses exploiting thermal states, distinguishable photons, and uniform distribution. The photonic quantum computer, <i>Jiuzhang</i>, generates up to 76 output photon clicks, which yields an output state-space dimension of 10³⁰ and a sampling rate that is faster than using the state-of-the-art simulation strategy and supercomputers by a factor of ~10¹⁴.