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Security of Quantum Key Distribution with Coherent States and Homodyne Detection

S. Iblisdir·G. Van Assche·N. J. Cerf
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Abstract

We assess the security of a quantum key distribution protocol relying on the transmission of Gaussian-modulated coherent states and homodyne detection. This protocol is shown to be equivalent to a squeezed state protocol based on a CSS code construction, and is thus provably secure against any eavesdropping strategy. We also briefly show how this protocol can be generalized in order to improve the net key rate.

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S. Iblisdir, G. Van Assche, N. J. Cerf. 2003-12-02. Security of Quantum Key Distribution with Coherent States and Homodyne Detection. https://doi.org/10.1103/physrevlett.93.170502

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