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Quantum cryptography

Continuous improvement

Using photons to disseminate encryption codes with complete security is one of the great successes of quantum information science. It has now been shown that long-distance cryptographic communication is just as effective when the scheme involves measuring the wave properties of light, rather than its particle properties.

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Figure 1: Quantum key distribution systems using DV single-photon state encoding (green) and CV quadrature-field amplitude encoding (red).


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Correspondence to P. K. Lam.

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Lam, P., Ralph, T. Continuous improvement. Nature Photon 7, 350–352 (2013).

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