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arXiv · 1605.05562

Backflash light characterization to prevent QKD zero-error hacking

A. Meda·I. P. Degiovanni·A. Tosi·Z. L. Yuan·G. Brida·M. Genovese
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Abstract

Single photon avalanche diodes (SPADs) are the most commercially diffused solution for single-photon counting in quantum key distribution (QKD) applications. However, the secondary photon emission, arising from the avalanche of charge carriers during a photon detection, may be exploited by an eavesdropper to gain information without forcing errors in the transmission key. In this paper, we characterise such backflash light in gated InGaAs/InP SPADs, and its spectral and temporal characterization for different detector models and different operating parameters. We qualitatively bound the maximum information leakage due to backflash light, and propose a solution.

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A. Meda, I. P. Degiovanni, A. Tosi, Z. L. Yuan, G. Brida, M. Genovese. 2016-05-18. Backflash light characterization to prevent QKD zero-error hacking. https://doi.org/10.1038/lsa.2016.261

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