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arXiv · 1806.05641

Implementation of a hybrid scheme for coherent plug-and-play quantum key distribution

Ignacio H. López Grande·Miguel A. Larotonda
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Abstract

We experimentally demonstrate a hybrid configuration for Quantum Key Distribution, that combines the simplicity of Distributed Phase Reference protocols with the self-referencing features and polarization insensitivity of the so-called Plug & Play system. Additionally, all the components are arranged in a server-client scheme to allow for practical key distribution. Blank, coherent pulse pair trains are generated at the reception end of the link by means of a pulse sequence and an unbalanced interferometer, and sent to the other end. The emitter writes the qubits by erasing one of the pulses from the pair as in a Coherent-One Way protocol. Detection, as well as eavesdropping monitoring is performed at the receiver side, using the same interferometer that was used to generate the initial phase-referenced pulses.

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Ignacio H. López Grande, Miguel A. Larotonda. 2018-06-14. Implementation of a hybrid scheme for coherent plug-and-play quantum key distribution. https://doi.org/10.1007/s11128-018-1941-7

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