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arXiv · 2507.09851

Evaluating a Multi-Color Entangled-Photon Source for a Bosonic Silicon Quantum Circuit

Koki Nagamachi·Hiroki Yamashita·Mikio Fujiwara·Shigehito Miki·Hirotaka Terai·Takafumi Ono
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Abstract

We evaluated a multi-color two-photon entangled state generated in silicon via spontaneous four-wave mixing (SFWM) as a potential source for bosonic integrated circuits. Spatially entangled photon states were created using a pair of silicon waveguides that produced signal and idler photons through SFWM, allowing us to observe quantum interference between them. Assuming that the frequencies of the multi-color photons were nearly identical, we characterized the generated quantum state by performing quantum state tomography on the bosonic system using a linear optical circuit. This study demonstrates the feasibility of using photon-pair sources generated in silicon via SFWM in bosonic optical circuits and highlights their potential for a wide range of applications in silicon-based optical quantum technologies.

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Koki Nagamachi, Hiroki Yamashita, Mikio Fujiwara, Shigehito Miki, Hirotaka Terai, Takafumi Ono. 2025-07-14. Evaluating a Multi-Color Entangled-Photon Source for a Bosonic Silicon Quantum Circuit. https://arxiv.org/abs/2507.09851

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