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arXiv · 1909.02975

Testing multi-photon interference on a silicon chip

Bryn A. Bell·Guillaume S. Thekkadath·Renyou Ge·Xinlun Cai·Ian A. Walmsley
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Abstract

Multi-photon interference in large multi-port interferometers is key to linear optical quantum computing and in particular to boson sampling. Silicon photonics enables complex interferometric circuits with many components in a small footprint and has the potential to extend these experiments to larger numbers of interfering modes. However, loss has generally limited the implementation of multi-photon experiments in this platform. Here, we make use of high-efficiency grating couplers to combine bright and pure quantum light sources based on ppKTP waveguides with silicon circuits. We interfere up to 5 photons in up to 15 modes, verifying genuine multi-photon interference by comparing the results against various models including partial distinguishability between photons.

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Bryn A. Bell, Guillaume S. Thekkadath, Renyou Ge, Xinlun Cai, Ian A. Walmsley. 2019-09-06. Testing multi-photon interference on a silicon chip. https://doi.org/10.1364/oe.27.035646

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