Quantum software for linear photonic simulations

The search for new, application-specific quantum computers designed to outperform any classical computer is driven by the ending of Moore's law and the quantum advantages potentially obtainable. Photonic networks are promising examples, with experimental demonstrations and potential for obtaining a quantum computer to solve problems believed classically impossible. This introduces a challenge: how does one design or understand such photonic networks? We develop novel complex phase-space software for simulating these photonic networks, and apply this to boson sampling experiments. Our techniques give sampling errors orders of magnitude lower than experimental measurements of correlations, for the same number of samples. We show that these techniques remove systematic errors in previous algorithms for estimating correlations, with order of magnitude improvements in errors in some cases. In addition to that, we obtain a scalable channel-combination strategy for assessment of boson sampling devices.