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arXiv · 1111.2798

Finite-key analysis of the six-state protocol with photon-number-resolution detectors

Silvestre Abruzzo·Markus Mertz·Hermann Kampermann·Dagmar Bruß
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Abstract

The six-state protocol is a discrete-variable protocol for quantum key distribution, that permits to tolerate a noisier channel than the BB84 protocol. In this work we provide a lower bound on the maximum achievable key rate of a practical implementation of the entanglement-based version of the six-state protocol. Regarding the experimental set-up we consider that the source is untrusted and the photon-number statistics is measured using photon-number-resolving detectors. We provide the formula for the key rate for a finite initial number of resources. As an illustration of the considered formalism, we calculate the key rate for the setting where the source produces entangled photon pairs via parametric down-conversion and the losses in the channel depend on the distance. As a result we find that the finite-key corrections for the considered scenario are not negligible and they should be considered in any practical analysis.

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Silvestre Abruzzo, Markus Mertz, Hermann Kampermann, Dagmar Bruß. 2011-11-11. Finite-key analysis of the six-state protocol with photon-number-resolution detectors. https://doi.org/10.1117/12.898049

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