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Efficient-phase-encoding protocols for continuous-variable quantum key distribution using coherent states and postselection

Ryo Namiki·Takuya Hirano
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Abstract

We propose efficient-phase-encoding protocols for continuous-variable quantum key distribution using coherent states and postselection. By these phase encodings, the probability of basis mismatch is reduced and total efficiency is increased. We also propose mixed-state protocols by omitting a part of classical communication steps in the efficient-phase-encoding protocols. The omission implies a reduction of information to an eavesdropper and possibly enhances the security of the protocols. We investigate the security of the protocols against individual beam splitting attack.

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Ryo Namiki, Takuya Hirano. 2006-08-18. Efficient-phase-encoding protocols for continuous-variable quantum key distribution using coherent states and postselection. https://doi.org/10.1103/physreva.74.032302

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