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arXiv · 2202.04316

Near perfect two-photon interference out a down-converter on a silicon photonic chip

Romain Dalidet·Florent Mazeas·Edgars Nitiss·Ozan Yakar·Anton Stroganov·Sébastien Tanzilli·Laurent Labonté·Camille-Sophie Brès
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Abstract

Integrated entangled photon-pair sources are key elements for enabling large-scale quantum photonic solutions, and addresses the challenges of both scaling-up and stability. Here we report the first demonstration of an energy-time entangled photon-pair source based on spontaneous parametric down-conversion in silicon-based platform through an optically induced second-order ($\chi^{(2)}$) nonlinearity, ensuring type-0 quasi-phase-matching of fundamental harmonic and its second-harmonic inside the waveguide. The developed source shows a coincidence-to-accidental ratio of 1635 at 8 of $\mu$W pump power. Remarkably, we report two-photon interference with near-perfect visibility of 99.36$\pm1.94\%$, showing high-quality photonic entanglement without excess background noise. This opens a new horizon for quantum technologies requiring the integration of a large variety of building functionalities on single chips.

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Romain Dalidet, Florent Mazeas, Edgars Nitiss, Ozan Yakar, Anton Stroganov, Sébastien Tanzilli, Laurent Labonté, Camille-Sophie Brès. 2022-02-09. Near perfect two-photon interference out a down-converter on a silicon photonic chip. https://doi.org/10.1364/oe.451621

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