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Unconditional security of the Bennett 1992 quantum key-distribution scheme with strong reference pulse

Kiyoshi Tamaki·Norbert Lütkenhaus·Masato Koashi·Jamie Batuwantudawe
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Abstract

We prove the unconditional security of the original Bennett 1992 protocol with strong reference pulse. We show that we may place a projection onto suitably defined qubit spaces before the receiver, which makes the analysis as simple as qubit-based protocols. Unlike the single-photon-based qubits, the qubits identified in this scheme are almost surely detected by the receiver even after a lossy channel. This leads to the key generation rate that is proportional to the channel transmission rate for proper choices of experimental parameters.

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Kiyoshi Tamaki, Norbert Lütkenhaus, Masato Koashi, Jamie Batuwantudawe. 2009-09-03. Unconditional security of the Bennett 1992 quantum key-distribution scheme with strong reference pulse. https://doi.org/10.1103/physreva.80.032302

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