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arXiv · 2204.06155

Countering detector manipulation attacks in quantum communication through detector self-testing

Lijiong Shen·Christian Kurtsiefer
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Abstract

In practical quantum key distribution systems, imperfect physical devices open security loopholes that challenge the core promise of this technology. Apart from various side channels, a vulnerability of single-photon detectors to blinding attacks has been one of the biggest concerns, and has been addressed both by technical means as well as advanced protocols. In this work, we present a countermeasure against such attacks based on self-testing of detectors to confirm their intended operation without relying on specific aspects of their inner working, and to reveal any manipulation attempts. We experimentally demonstrate this countermeasure with a typical InGaAs avalanche photodetector, but the scheme can be easily implemented with any single photon detector.

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Lijiong Shen, Christian Kurtsiefer. 2022-04-13. Countering detector manipulation attacks in quantum communication through detector self-testing. https://doi.org/10.1063/5.0233772

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