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arXiv · 2505.10338

Telecom-to-Visible Quantum Frequency Converter on a Silicon Nitride Chip

Sidarth Raghunathan·Richard Oliver·Yun Zhao·Karl McNulty·Chaitali Joshi·Michal Lipson·Alexander L. Gaeta
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Abstract

Quantum frequency conversion serves a key role in the realization of hybrid quantum networks by interfacing between wavelength-incompatible platforms. Here we present the first quantum frequency converter connecting visible and telecom domains on a silicon nitride (SiN) chip, using Bragg-scattering four-wave mixing to upconvert heralded single photons from 1260 to 698 nm, which covers a 192 THz span. We examine the noise sources in SiN and devise approaches to suppress noise photons at the source and target frequencies to enable measurements at the single-photon level. We demonstrate an on-chip conversion efficiency of 5% in photon flux and describe design modifications that can be implemented to significantly improve it. Our results pave the way for the implementation of CMOS-compatible devices in quantum networks.

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Sidarth Raghunathan, Richard Oliver, Yun Zhao, Karl McNulty, Chaitali Joshi, Michal Lipson, Alexander L. Gaeta. 2025-05-15. Telecom-to-Visible Quantum Frequency Converter on a Silicon Nitride Chip. https://doi.org/10.1364/opticaq.563123

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