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arXiv · 2310.20107

Preparing a commercial quantum key distribution system for certification against implementation loopholes

Vadim Makarov·Alexey Abrikosov·Poompong Chaiwongkhot·Aleksey K. Fedorov·Anqi Huang·Evgeny Kiktenko·Mikhail Petrov·Anastasiya Ponosova·Daria Ruzhitskaya·Andrey Tayduganov·Daniil Trefilov·Konstantin Zaitsev
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Abstract

A commercial quantum key distribution (QKD) system needs to be formally certified to enable its wide deployment. The certification should include the system's robustness against known implementation loopholes and attacks that exploit them. Here we ready a fiber-optic QKD system for this procedure. The system has a prepare-and-measure scheme with decoy-state BB84 protocol, polarisation encoding, qubit source rate of 312.5 MHz, and is manufactured by QRate. We detail its hardware and post-processing. We analyse the hardware for known implementation loopholes, search for possible new loopholes, and discuss countermeasures. We then amend the system design to address the highest-risk loopholes identified. We also work out technical requirements on the certification lab and outline its possible structure.

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Vadim Makarov, Alexey Abrikosov, Poompong Chaiwongkhot, Aleksey K. Fedorov, Anqi Huang, Evgeny Kiktenko, Mikhail Petrov, Anastasiya Ponosova, Daria Ruzhitskaya, Andrey Tayduganov, Daniil Trefilov, Konstantin Zaitsev. 2023-10-31. Preparing a commercial quantum key distribution system for certification against implementation loopholes. https://doi.org/10.1103/physrevapplied.22.044076

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