Optics and Spectroscopy

, Volume 111, Issue 5, pp 673–677 | Cite as

Classical correlations can enhance the continuous-variable quantum key distribution

Quantum Communication


We address the effect of classical correlations, introduced to a quantum resource used for the continuous-variable quantum key distribution. The set-up is based on an entangled source with two trusted parties performing homodyne measurements on their modes, thus corresponding to the preparation of squeezed states, while one of the modes is traveling to the remote party through lossy and noisy channel. The security of the scheme is considered against individual and collective eavesdropping attacks. It is shown that the classical correlations added to the entangled source increase the performance of the scheme both quantatively in terms of the secure key rate and qualitatively in terms of the security region with respect to the tolerable excess noise for both types of attacks and the improvement is essentially significant for sources possessing low degree of nonclassicality.


Classical Correlation Security Region Individual Attack Lossy Channel Collective Attack 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    C. H. Bennett and G. Brassard, in Proceedings of the IEEE International Conference on Computers, Systems, and Signal Processing (IEEE, New York, 1984), pp. 175–179; for overview: N. Gisin et al., Rev. Mod. Phys. 74, 145 (2002).Google Scholar
  2. 2.
    S. L. Braunstein and P. van Loock, Rev. Mod. Phys. 77, 513 (2005).CrossRefMATHADSGoogle Scholar
  3. 3.
    F. Grosshans et al., Nature (London) 421, 238 (2003); F. Grosshans et al., Quantum Inf. Comput. 3, 535 (2003).CrossRefADSGoogle Scholar
  4. 4.
    F. Grosshans, Phys. Rev. Lett. 94, 020504 (2005); M. Navascues and A. Acin, Phys. Rev. Lett. 94, 020505 (2005).CrossRefADSGoogle Scholar
  5. 5.
    M. Navascues et al., Phys. Rev. Lett. 97, 190502 (2006); R. Garcia-Patron and N. J. Cerf, Phys. Rev. Lett. 97, 190503 (2006).CrossRefADSGoogle Scholar
  6. 6.
    J. Lodewyck et al., Phys. Rev. A 72, 050303 (2005); J. Lodewyck et al., Phys. Rev. A 76, 042305 (2007).CrossRefADSGoogle Scholar

Copyright information

© Pleiades Publishing, Ltd. 2011

Authors and Affiliations

  1. 1.Bogolyubov Institute for Theoretical Physics of National Academy of SciencesKievUkraine
  2. 2.Department of OpticsPalacký UniversityOlomoucCzech Republic

Personalised recommendations