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arXiv · 1408.4566

Complete elimination of information leakage in continuous-variable quantum communication channels

Christian S. Jacobsen·Lars S. Madsen·Vladyslav C. Usenko·Radim Filip·Ulrik L. Andersen
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Abstract

In all lossy communication channels realized to date, information is inevitably leaked to a potential eavesdropper. Here we present a communication protocol that does not allow for any information leakage to a potential eavesdropper in a purely lossy channel. By encoding information into a restricted Gaussian alphabet of squeezed states we show, both theoretically and experimentally, that the Holevo information between the eavesdropper and the intended recipient can be exactly zero in a purely lossy channel while minimized in a noisy channel. This result is of fundamental interest, but might also have practical implications in extending the distance of secure quantum key distribution.

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Christian S. Jacobsen, Lars S. Madsen, Vladyslav C. Usenko, Radim Filip, Ulrik L. Andersen. 2014-08-20. Complete elimination of information leakage in continuous-variable quantum communication channels. https://doi.org/10.1038/s41534-018-0084-0

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