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Single photon quantum cryptography

Alexios Beveratos·Rosa Brouri·Thierry Gacoin·Andre Villing·Jean-Philippe Poizat·Philippe Grangier
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Abstract

We report the full implementation of a quantum cryptography protocol using a stream of single photon pulses generated by a stable and efficient source operating at room temperature. The single photon pulses are emitted on demand by a single nitrogen-vacancy (NV) color center in a diamond nanocrystal. The quantum bit error rate is less that 4.6% and the secure bit rate is 9500 bits/s. The overall performances of our system reaches a domain where single photons have a measurable advantage over an equivalent system based on attenuated light pulses.

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Alexios Beveratos, Rosa Brouri, Thierry Gacoin, Andre Villing, Jean-Philippe Poizat, Philippe Grangier. 2002-06-19. Single photon quantum cryptography. https://doi.org/10.1103/physrevlett.89.187901

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