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arXiv · 0711.4631

On Secure Quantum Key Distribution Using Continuous Variables of Single Photons

Lijian Zhang·Christine Silberhorn·Ian A. Walmsley
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Abstract

We analyse the distribution of secure keys using quantum cryptography based on the continuous variable degree of freedom of entangled photon pairs. We derive the information capacity of a scheme based on the spatial entanglement of photons from a realistic source, and show that the standard measures of security known for quadrature-based continuous variable quantum cryptography (CV-QKD) are inadequate. A specific simple eavesdropping attack is analysed to illuminate how secret information may be distilled well beyond the bounds of the usual CV-QKD measures.

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Lijian Zhang, Christine Silberhorn, Ian A. Walmsley. 2007-11-29. On Secure Quantum Key Distribution Using Continuous Variables of Single Photons. https://doi.org/10.1103/physrevlett.100.110504

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