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arXiv · 1112.2179

Continuous Variable Quantum Key Distribution: Finite-Key Analysis of Composable Security against Coherent Attacks

Fabian Furrer·Torsten Franz·Mario Berta·Anthony Leverrier·Volkher B. Scholz·Marco Tomamichel·Reinhard F. Werner
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Abstract

We provide a security analysis for continuous variable quantum key distribution protocols based on the transmission of squeezed vacuum states measured via homodyne detection. We employ a version of the entropic uncertainty relation for smooth entropies to give a lower bound on the number of secret bits which can be extracted from a finite number of runs of the protocol. This bound is valid under general coherent attacks, and gives rise to keys which are composably secure. For comparison, we also give a lower bound valid under the assumption of collective attacks. For both scenarios, we find positive key rates using experimental parameters reachable today.

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Fabian Furrer, Torsten Franz, Mario Berta, Anthony Leverrier, Volkher B. Scholz, Marco Tomamichel, Reinhard F. Werner. 2014-01-20. Continuous Variable Quantum Key Distribution: Finite-Key Analysis of Composable Security against Coherent Attacks. https://doi.org/10.1103/physrevlett.109.100502%3B%2010.1103%2Fphysrevlett.112.019902

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