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arXiv · 2512.09390

Compact and efficient quantum frequency conversion of a fiber-pigtailed single-photon source

Mathis Cohen·Anthony Martin·Romain Dalidet·Florian Pastier·Marie Billard·Aristide Lemaitre·Valérian Giesz·Niccolo Somaschi·Sarah Thomas·Pascale Senellart-Mardon·Sébastien Tanzilli·Laurent Labonté
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Abstract

Quantum frequency converters are key enabling technologies in photonic quantum information science to bridge the gap between quantum emitters and telecom photons. Here, we report a coherent frequency converter scheme combining a fiber-coupled nonlinear optical Lithium Niobate waveguide with a fiber-pigtailed single-photon source based on semiconductor quantum dots. Single and indistinguishable photons are converted from 925.7 nm to the telecommunication C-band, with a 48.4% end-to-end efficiency and full preservation of single-photon purity and indistinguishability. The integration of the two fiber-based modules achieving top-level performance represents an important step toward the practical interconnection of future quantum information processing systems operating at different wavelengths.

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Mathis Cohen, Anthony Martin, Romain Dalidet, Florian Pastier, Marie Billard, Aristide Lemaitre, Valérian Giesz, Niccolo Somaschi, Sarah Thomas, Pascale Senellart-Mardon, Sébastien Tanzilli, Laurent Labonté. 2025-12-10. Compact and efficient quantum frequency conversion of a fiber-pigtailed single-photon source. https://arxiv.org/abs/2512.09390

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