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arXiv · 2610.38048

Continuous variable quantum key distribution through a fading channel with minimal information leakage

Josephine Dias·Timothy C. Ralph
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Abstract

Continuous variable quantum key distribution enables two parties to extract provably secure keys for cryptography by exploiting aspects of quantum mechanics. A central challenge in achieving QKD over long distances is overcoming optical loss, which limits the secret key rates and achievable transmission distances. Recent work has illustrated how to perform continuous variable quantum key distribution while eliminating information leakage to an eavesdropper in a pure-loss channel and minimizing information leakage in a noisy channel. In this work, we analyse this protocol under conditions where the quantum channel linking the sender and receiver is a fading channel, which can be used to model free-space links. We find that the protocol maintains strong performance over fading channels and outperforms comparable protocols.

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Josephine Dias, Timothy C. Ralph. 2026-10-27. Continuous variable quantum key distribution through a fading channel with minimal information leakage. https://arxiv.org/abs/2610.38048

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