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arXiv · 2506.05989

An optical frequency shifter based on continuous-wave pump fields

Anica Hamer·Frank Vewinger·Michael H. Frosz·Simon Stellmer
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Abstract

Practical implementations of quantum information networks require frequency conversion of individual photons. Approaches based on a molecular gas as the nonlinear medium cover a wide range of the optical spectrum and promise high efficiency at negligible background. We present polarization-preserving frequency conversion in a hydrogen-loaded hollow core fiber using continuous-wave pump fields. We demonstrate conversion efficiency at the level of a few per mille, discuss various limitations and loss mechanisms, and present a route to increase conversion efficiency to near unity.

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Anica Hamer, Frank Vewinger, Michael H. Frosz, Simon Stellmer. 2025-06-06. An optical frequency shifter based on continuous-wave pump fields. https://arxiv.org/abs/2506.05989

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