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arXiv · 1408.5012

Teleportation-Based Continuous Variable Quantum Cryptography

F. S. Luiz·Gustavo Rigolin
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Abstract

We present a continuous variable (CV) quantum key distribution (QKD) scheme based on the CV quantum teleportation of coherent states that yields a raw secret key made up of discrete variables for both Alice and Bob. This protocol preserves the efficient detection schemes of current CV technology (no single-photon detection techniques) and, at the same time, has efficient error correction and privacy amplification schemes due to the binary modulation of the key. We show that for a certain type of incoherent attack it is secure for almost any value of the transmittance of the optical line used by Alice to share entangled two-mode squeezed states with Bob (no 3 dB or 50% loss limitation characteristic of beam splitting attacks). The present CVQKD protocol works deterministically (no postselection needed) with efficient direct reconciliation techniques (no reverse reconciliation) in order to generate a secure key and beyond the 50% loss case at the incoherent attack level.

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F. S. Luiz, Gustavo Rigolin. 2017-01-30. Teleportation-Based Continuous Variable Quantum Cryptography. https://doi.org/10.1007/s11128-016-1504-8

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