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4 states protocol for time coding quantum key distribution

Thierry Debuisschert·William Boucher
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Abstract

Coherent one photon pulses are sent with four possible time delays with respect to a reference. Ambiguity of the photon time detection resulting from pulses overlap combined with interferometric measurement allows for secure key exchange.

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Thierry Debuisschert, William Boucher. 2003-09-18. 4 states protocol for time coding quantum key distribution. https://arxiv.org/abs/quant-ph/0309139

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