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arXiv · 1603.06620

Sufficiency of quantum non-Gaussianity for discrete-variable quantum key distribution over noisy channel

Mikołaj Lasota·Radim Filip·Vladyslav C. Usenko
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Abstract

Quantum key distribution can be enhanced and extended if nonclassical single-photon states of light are used. We study a connection between the security of quantum key distribution and quantum non-Gaussianity of light arriving at the receiver's detection system after the propagation through a noisy quantum channel, being under full control of an eavesdropper performing general collective attacks. We show that while quantum nonclassicality exhibited by the light arriving at the receiver's station is a necessary indication of the security of the discrete-variable protocols, quantum non-Gaussianity can be a sufficient indication of their security. Therefore, checking for non-Gaussianity of this light by performing standard autocorrelation function measurement can be used for prior verification of the usability of prepare-and-measure schemes. It can play similar role to the prior verification of the quantum correlations sufficient to violate Bell inequalities for entanglement-based protocols.

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Mikołaj Lasota, Radim Filip, Vladyslav C. Usenko. 2017-07-12. Sufficiency of quantum non-Gaussianity for discrete-variable quantum key distribution over noisy channel. https://doi.org/10.1103/physreva.96.012301

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