Longer distance continuous variable quantum key distribution protocol with photon subtraction at the receiver

  • Kyongchun LimEmail author
  • Changho Suh
  • June-Koo Kevin Rhee


One of the limitations of continuous variable quantum key distribution is the relatively short transmission distance of secure keys. Some solutions have been proposed to overcome the limitation including reverse reconciliation, trusted noise concept, and non-Gaussian operation. In this paper, we propose a protocol using photon subtraction at the receiver, which combines the synergetic benefits of the aforementioned approaches. Using simulations, we show that the performance of the proposed protocol outperforms other conventional protocols. The results showed that an improvement in secure key distance can be obtained using a non-Gaussian operation, depending on the position where the operation is performed, similar to the trusted noise concept. Furthermore, the result implies existence of some Gaussian operations which increases security without using a beam splitter.


Quantum cryptography Continuous variable quantum key distribution Non-Gaussian state Quantum information and processing 



This work was supported by the ICT R&D program of MSIT/IITP (1711073835, Reliable crypto-system standards and core technology development for secure quantum key distribution network) and the MSIT (Ministry of Science and ICT), Korea, under the ITRC (Information Technology Research Center) support program (IITP-2018-2018-0-01402) supervised by the IITP (Institute for Information & communications Technology Promotion).


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Kyongchun Lim
    • 1
    Email author
  • Changho Suh
    • 1
  • June-Koo Kevin Rhee
    • 1
  1. 1.School of Electrical EngineeringKorea Advanced Institute of Science and TechnologyDaejeonKorea

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