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arXiv · 2301.10270

Improved composable key rates for CV-QKD

Stefano Pirandola·Panagiotis Papanastasiou
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Abstract

Modern security proofs of quantum key distribution (QKD) must take finite-size effects and composable aspects into consideration. This is also the case for continuous-variable (CV) protocols which are based on the transmission and detection of bosonic coherent states. In this paper, we refine and advance the previous theory in this area providing a more rigorous formulation for the composable key rate of a generic CV-QKD protocol. Thanks to these theoretical refinements, our general formulas allow us to prove more optimistic key rates with respect to previous literature.

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quant-phphysics.app-phphysics.comp-ph

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BibTeXRIS

Stefano Pirandola, Panagiotis Papanastasiou. 2023-01-24. Improved composable key rates for CV-QKD. https://doi.org/10.1103/physrevresearch.6.023321

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