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arXiv · 2103.02109

Quantum circuits with many photons on a programmable nanophotonic chip

J. M. Arrazola·V. Bergholm·K. Brádler·T. R. Bromley·M. J. Collins·I. Dhand·A. Fumagalli·T. Gerrits·A. Goussev·L. G. Helt·J. Hundal·T. Isacsson·R. B. Israel·J. Izaac·S. Jahangiri·R. Janik·N. Killoran·S. P. Kumar·J. Lavoie·A. E. Lita·D. H. Mahler·M. Menotti·B. Morrison·S. W. Nam·L. Neuhaus·H. Y. Qi·N. Quesada·A. Repingon·K. K. Sabapathy·M. Schuld·D. Su·J. Swinarton·A. Száva·K. Tan·P. Tan·V. D. Vaidya·Z. Vernon·Z. Zabaneh·Y. Zhang
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Abstract

Growing interest in quantum computing for practical applications has led to a surge in the availability of programmable machines for executing quantum algorithms. Present day photonic quantum computers have been limited either to non-deterministic operation, low photon numbers and rates, or fixed random gate sequences. Here we introduce a full-stack hardware-software system for executing many-photon quantum circuits using integrated nanophotonics: a programmable chip, operating at room temperature and interfaced with a fully automated control system. It enables remote users to execute quantum algorithms requiring up to eight modes of strongly squeezed vacuum initialized as two-mode squeezed states in single temporal modes, a fully general and programmable four-mode interferometer, and genuine photon number-resolving readout on all outputs. Multi-photon detection events with photon numbers and rates exceeding any previous quantum optical demonstration on a programmable device are made possible by strong squeezing and high sampling rates. We verify the non-classicality of the device output, and use the platform to carry out proof-of-principle demonstrations of three quantum algorithms: Gaussian boson sampling, molecular vibronic spectra, and graph similarity.

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J. M. Arrazola, V. Bergholm, K. Brádler, T. R. Bromley, M. J. Collins, I. Dhand, A. Fumagalli, T. Gerrits, A. Goussev, L. G. Helt, J. Hundal, T. Isacsson, R. B. Israel, J. Izaac, S. Jahangiri, R. Janik, N. Killoran, S. P. Kumar, J. Lavoie, A. E. Lita, D. H. Mahler, M. Menotti, B. Morrison, S. W. Nam, L. Neuhaus, H. Y. Qi, N. Quesada, A. Repingon, K. K. Sabapathy, M. Schuld, D. Su, J. Swinarton, A. Száva, K. Tan, P. Tan, V. D. Vaidya, Z. Vernon, Z. Zabaneh, Y. Zhang. 2021-03-03. Quantum circuits with many photons on a programmable nanophotonic chip. https://doi.org/10.1038/s41586-021-03202-1

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