Continuous variable quantum key distribution: Beating the 3 DB loss limit

Norbert Lütkenhaus, Christine Silberhorn, Gerd Leuchs, Timothy C. Ralph

Published Jan 1, 2003• 0 citations

Abstract

We demonstrate that quantum key distribution systems based on continuous variable implementations can operate beyond the apparent 3 dB loss limit that is implied by the beam splitting attack. Here we discuss the information-theoretical background and explain the difference between our approach and that by Grosshans and Grangier.

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