Back to News
quantum-computing

Practical Methods for Distance-Adaptive Continuous-Variable Quantum Key Distribution

arXiv Quantum Physics
Loading...
4 min read
0 likes
⚡ Quantum Brief
Researchers from multiple institutions propose solutions to extend the operational range of continuous-variable quantum key distribution (CV-QKD), which faces strict distance limits due to fixed-rate error correction. The study identifies three practical methods: adjusting modulation variance, introducing controlled detector loss, and implementing rate-adaptive forward error correction (FEC), all experimentally validated. While the first two methods extend distance without new hardware, they significantly reduce secret key rates, making them less efficient for real-world deployment. Rate-adaptive FEC emerges as the most effective approach, achieving near-optimal performance across varying distances when reconciliation efficiency is properly calibrated. The findings highlight critical trade-offs between distance, hardware complexity, and key generation rates, advancing CV-QKD’s viability in deployed optical networks.
Practical Methods for Distance-Adaptive Continuous-Variable Quantum Key Distribution

Summarize this article with:

Quantum Physics arXiv:2603.10480 (quant-ph) [Submitted on 11 Mar 2026] Title:Practical Methods for Distance-Adaptive Continuous-Variable Quantum Key Distribution Authors:Jonas Berl, Utku Akin, Erdem Eray Cil, Laurent Schmalen, Tobias Fehenberger View a PDF of the paper titled Practical Methods for Distance-Adaptive Continuous-Variable Quantum Key Distribution, by Jonas Berl and 4 other authors View PDF HTML (experimental) Abstract:Continuous-variable quantum key distribution (CV-QKD) is a promising quantum-safe alternative to classical asymmetric cryptography that enables two authenticated parties to establish a shared secret over a potentially eavesdropped quantum channel. A key step in CV-QKD post-processing is information reconciliation, which leverages forward error correction (FEC) techniques to extract identical bit strings from noisy correlated data. In this work, we analyze the strict limitations on operating distance that are imposed by constant-rate FEC, severely limiting the practicability of CV-QKD systems in deployed optical networks. To overcome the distance limitations, we evaluate three strategies: (i) tuning modulation variance, (ii) adding controlled amounts of trusted detector loss, and (iii) the use of rate-adaptive FEC. All approaches are validated experimentally, compared in terms of performance, and we discuss implementation aspects. Our results show that while methods (i) and (ii) extend the operational distance of constant-rate FEC without the need for additional hardware components, they incur a significant penalty in secret key rate (SKR). In contrast, rate-adaptive FEC enables CV-QKD operation with performance close to the asymptotic SKR over a wide range of distances, provided that the reconciliation efficiency is chosen appropriately. Comments: Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2603.10480 [quant-ph] (or arXiv:2603.10480v1 [quant-ph] for this version) https://doi.org/10.48550/arXiv.2603.10480 Focus to learn more arXiv-issued DOI via DataCite Related DOI: https://doi.org/10.1109/JLT.2026.3664474 Focus to learn more DOI(s) linking to related resources Submission history From: Jonas Berl [view email] [v1] Wed, 11 Mar 2026 07:09:01 UTC (990 KB) Full-text links: Access Paper: View a PDF of the paper titled Practical Methods for Distance-Adaptive Continuous-Variable Quantum Key Distribution, by Jonas Berl and 4 other authorsView PDFHTML (experimental)TeX Source view license Current browse context: quant-ph new | recent | 2026-03 References & Citations INSPIRE HEP NASA ADSGoogle Scholar Semantic Scholar export BibTeX citation Loading... BibTeX formatted citation × loading... Data provided by: Bookmark Bibliographic Tools Bibliographic and Citation Tools Bibliographic Explorer Toggle Bibliographic Explorer (What is the Explorer?) Connected Papers Toggle Connected Papers (What is Connected Papers?) Litmaps Toggle Litmaps (What is Litmaps?) scite.ai Toggle scite Smart Citations (What are Smart Citations?) Code, Data, Media Code, Data and Media Associated with this Article alphaXiv Toggle alphaXiv (What is alphaXiv?) Links to Code Toggle CatalyzeX Code Finder for Papers (What is CatalyzeX?) DagsHub Toggle DagsHub (What is DagsHub?) GotitPub Toggle Gotit.pub (What is GotitPub?) Huggingface Toggle Hugging Face (What is Huggingface?) Links to Code Toggle Papers with Code (What is Papers with Code?) ScienceCast Toggle ScienceCast (What is ScienceCast?) Demos Demos Replicate Toggle Replicate (What is Replicate?) Spaces Toggle Hugging Face Spaces (What is Spaces?) Spaces Toggle TXYZ.AI (What is TXYZ.AI?) Related Papers Recommenders and Search Tools Link to Influence Flower Influence Flower (What are Influence Flowers?) Core recommender toggle CORE Recommender (What is CORE?) Author Venue Institution Topic About arXivLabs arXivLabs: experimental projects with community collaborators arXivLabs is a framework that allows collaborators to develop and share new arXiv features directly on our website. Both individuals and organizations that work with arXivLabs have embraced and accepted our values of openness, community, excellence, and user data privacy. arXiv is committed to these values and only works with partners that adhere to them. Have an idea for a project that will add value for arXiv's community? Learn more about arXivLabs. Which authors of this paper are endorsers? | Disable MathJax (What is MathJax?)

Read Original

Tags

quantum-networking
post-quantum-cryptography
quantum-key-distribution
partnership

Source Information

Source: arXiv Quantum Physics