Continuous variable quantum cryptography: beating the 3 dB loss limit.

By Christine Silberhorn, Timothy C. Ralph, Norbert Lutkenhaus, Gerd Leuchs. Physical Review Letters, 2002

313 citations recorded by the source corpus.

We demonstrate that secure quantum key distribution systems based on continuous variable implementations can operate beyond the apparent 3 dB loss limit that is implied by the beam splitting attack. The loss limit was established for standard minimum uncertainty states such as coherent states. We show that, by an appropriate postselection mechanism, we can enter a region where Eve's knowledge on Alice's key falls behind the information shared between Alice and Bob, even in the presence of substantial losses.

Subfields: Artificial Intelligence, Atomic and Molecular Physics, and Optics

View Paper: https://www.semanticscholar.org/paper/5ceabd7e8f61b76eaa228616eac2194324f5502b

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In Artificial Intelligence

In Atomic and Molecular Physics, and Optics

Citations in the corpus

Continuous-variable optical quantum-state tomography (2009, background): “Time-domain homodyning is also an essential element of continuous-variable quantum cryptography Grosshans and Grander, 2002; Silberhorn et al., 2002; Funk, 2004; Lodewyck et al., 2007 .”
The Impact of Quantum Computing on Present Cryptography (2018, background): “• Discrete-modulation protocols ◦ First continuous variable protocol based on coherent states instead of squeezed states [45].”
Distributing Secret Keys with Quantum Continuous Variables: Principle, Security and Implementations (2015, methodology): “Other protocols have been investigated in the literature: two-way protocols [13,14], protocols with a non-Gaussian modulation [15–19] or post-selection [20]; but, their security analysis is less advanced, and we will not consider them further in this short review.”
The security of practical quantum key distribution (2008, methodology): “…notably continuousvariable protocols (Cerf, Lévy and Van Assche, 2001; Gottesman and Preskill, 2001; Grosshans and Grangier, 2002a; Hillery, 2000; Ralph, 1999; Silberhorn et al., 2002) and the more recent distributed-phase-reference protocols (Inoue, Waks and Yamamoto, 2002; Stucki et al., 2005).”
Advances in quantum cryptography (2019, unknown): “The first discrete-modulated CV-QKD protocol was based on a binary encoding of coherent states [424] and was designed to overcome the 3dB limitation of CV-QKD in DR.”