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arXiv · 0712.3823

Multidimensional reconciliation for continuous-variable quantum key distribution

Anthony Leverrier·Romain Alléaume·Joseph Boutros·Gilles Zémor·Philippe Grangier
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Abstract

We propose a method for extracting an errorless secret key in a continuous-variable quantum key distribution protocol, which is based on Gaussian modulation of coherent states and homodyne detection. The crucial feature is an eight-dimensional reconciliation method, based on the algebraic properties of octonions. Since the protocol does not use any postselection, it can be proven secure against arbitrary collective attacks, by using well-established theorems on the optimality of Gaussian attacks. By using this new coding scheme with an appropriate signal to noise ratio, the distance for secure continuous-variable quantum key distribution can be significantly extended.

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Anthony Leverrier, Romain Alléaume, Joseph Boutros, Gilles Zémor, Philippe Grangier. 2008-07-03. Multidimensional reconciliation for continuous-variable quantum key distribution. https://doi.org/10.1103/physreva.77.042325

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