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arXiv · 1002.0953

Security and entanglement in differential-phase-shift quantum key distribution

Adriana Marais·Thomas Konrad·Francesco Petruccione
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Abstract

The differential-phase-shift quantum key distribution protocol is formalised as a prepare-and-measure scheme and translated into an equivalent entanglement-based protocol. A necessary condition for security is that Bob's measurement can detect the entanglement of the distributed state in the entanglement-based translation, which implies that his measurement is described by non-commuting POVM elements. This condition is shown to be met.

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Adriana Marais, Thomas Konrad, Francesco Petruccione. 2010-02-04. Security and entanglement in differential-phase-shift quantum key distribution. https://arxiv.org/abs/1002.0953

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