PaperSwipe

Decoy-state quantum key distribution over 227 km with a frequency-converted telecom single-photon source

Published 1 day agoVersion 1arXiv:2512.05101

Authors

Frederik Brooke Barnes, Roberto G. Pousa, Christopher L. Morrison, Zhe Xian Koong, Joseph Ho, Francesco Graffitti, John Jeffers, Daniel K. L. Oi, Brian D. Gerardot, Alessandro Fedrizzi

Categories

quant-ph

Abstract

We implement a decoy-state quantum key distribution scheme using a telecom C-band single-emitter source. The decoy states are created by varying the optical excitation of the quantum emitter to modulate the photon number distribution. We provide an analysis of our scheme based on existing security proofs, allowing the calculation of secret key rates including finite key effects. This enables us to demonstrate, with a realistic single-photon source, positive secret key rates using our scheme over 227 km of optical fiber, equivalent to a loss tolerance one order of magnitude greater than non-decoy schemes. This work broadens the scope of single-photon sources in future quantum networks by enabling long-distance QKD with realistic levels of single-photon purity.

Decoy-state quantum key distribution over 227 km with a frequency-converted telecom single-photon source

1 day ago
v1
10 authors

Categories

quant-ph

Abstract

We implement a decoy-state quantum key distribution scheme using a telecom C-band single-emitter source. The decoy states are created by varying the optical excitation of the quantum emitter to modulate the photon number distribution. We provide an analysis of our scheme based on existing security proofs, allowing the calculation of secret key rates including finite key effects. This enables us to demonstrate, with a realistic single-photon source, positive secret key rates using our scheme over 227 km of optical fiber, equivalent to a loss tolerance one order of magnitude greater than non-decoy schemes. This work broadens the scope of single-photon sources in future quantum networks by enabling long-distance QKD with realistic levels of single-photon purity.

Authors

Frederik Brooke Barnes, Roberto G. Pousa, Christopher L. Morrison et al. (+7 more)

arXiv ID: 2512.05101
Published Dec 4, 2025

Click to preview the PDF directly in your browser