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Security of Continuous-variable quantum cryptography using coherent states: Decline of postselection advantage

Ryo Namiki·Takuya Hirano
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Abstract

We investigate the security of continuous-variable (CV) quantum key distribution (QKD) using coherent states in the presence of quadrature excess noise. We consider an eavesdropping attack which uses a linear amplifier and beam splitter. This attack makes a link between beam-splitting attack and intercept-resend attack (classical teleportation attack). We also show how postselection loses its efficiency in a realistic channel.

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Ryo Namiki, Takuya Hirano. 2005-06-23. Security of Continuous-variable quantum cryptography using coherent states: Decline of postselection advantage. https://doi.org/10.1103/physreva.72.024301

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