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arXiv · 1605.04536

Finite-key analysis of a practical decoy-state high-dimensional quantum key distribution

Haize Bao·Wansu Bao·Yang Wang·Chun Zhou·Ruike Chen
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Abstract

Compared with two-level quantum key distribution (QKD), highdimensional QKD enable two distant parties to share a secret key at a higher rate. We provide a finite-key security analysis for the recently proposed practical highdimensional decoy-state QKD protocol based on time-energy entanglement. We employ two methods to estimate the statistical fluctuation of the postselection probability and give a tighter bound on the secure-key capacity. By numerical evaluation, we show the finite-key effect on the secure-key capacity in different conditions. Moreover, our approach could be used to optimize parameters in practical implementations of highdimensional QKD.

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Haize Bao, Wansu Bao, Yang Wang, Chun Zhou, Ruike Chen. 2016-05-15. Finite-key analysis of a practical decoy-state high-dimensional quantum key distribution. https://doi.org/10.1088/1751-8113%2F49%2F20%2F205301

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