Deterministic QKD source robust against side-channel attacks

Abstract:Quantum key distribution (QKD) is secure in principle, but practical security can be undermined by discrepancies between real devices and the idealized models assumed in security proofs. Source side channels, including those exploited by Trojan-horse attacks, are particularly detrimental: neglecting them compromises implementation security, whereas accounting for them reduces performance. Here we propose a QKD source that is intrinsically robust against side-channel attacks. Unlike existing passive and modulator-free schemes, it requires neither post-selection of the emitted pulses nor devices with a perfect extinction ratio to suppress side channels, and it does not introduce correlations between the intensity and the encoded bit or basis. Consequently, simpler security proofs apply directly, yielding substantially higher key rates. Our proposal appears to be within reach of current technology and therefore provides a clear and practical path toward implementation-secure QKD.

arXiv:2607.28063 [quant-ph]

(or arXiv:2607.28063v1 [quant-ph] for this version)

https://doi.org/10.48550/arXiv.2607.28063 Focus to learn more arXiv-issued DOI via DataCite (pending registration)

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.