Experimental composable key distribution using discrete-modulated continuous variable quantum cryptography

Adnan A. E. Hajomer; Florian Kanitschar; Nitin Jain; Michael Hentschel; Runjia Zhang; Norbert Lütkenhaus; Ulrik L. Andersen; Christoph Pacher; Tobias Gehring

doi:10.1038/s41377-025-01924-9

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Experimental composable key distribution using discrete-modulated continuous variable quantum cryptography

Original Articles

- Experimental composable key distribution using discrete-modulated continuous variable quantum cryptography
- Light: Science & Applications Vol. 14, Issue 9, Pages: 2696-2708(2025)
- Affiliations：
  
  1.Center for Macroscopic Quantum States (bigQ), Department of Physics, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
  2.Vienna Center for Quantum Science and Technology (VCQ), Atominstitut, Technische Universität Wien, Stadionallee 2, 1020 Vienna, Austria
  3.AIT Austrian Institute of Technology, Center for Digital Safety & Security, Giefinggasse 4, 1210 Vienna, Austria
  4.Institute for Quantum Computing and Department of Physics and Astronomy, University of Waterloo, Waterloo, ON N2L 3G1, Canada
  5.FragmentiX Storage Solutions GmbH, Wohllebengasse 10/7, 1040 Vienna, Austria
- Author bio：
  
  Adnan A. E. Hajomer (aaeha@dtu.dk)
  Tobias Gehring (tobias.gehring@fysik.dtu.dk)
- Funds：
- DOI：10.1038/s41377-025-01924-9
  CLC：
- Received：10 March 2025，
  
  Revised：2025-06-13，
  
  Accepted：18 June 2025，
  
  Published Online：28 July 2025，
  
  Published：30 September 2025
- Accepted：
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Hajomer, A. A. E. et al. Experimental composable key distribution using discrete-modulated continuous variable quantum cryptography. Light: Science & Applications, 14, 2696-2708 (2025).
DOI：

Hajomer, A. A. E. et al. Experimental composable key distribution using discrete-modulated continuous variable quantum cryptography. Light: Science & Applications, 14, 2696-2708 (2025). DOI： 10.1038/s41377-025-01924-9.

摘要

Abstract

Establishing secure data communication necessitates secure key exchange over a public channel. Quantum key distribution (QKD)

which leverages the principles of quantum physics

can achieve this with information-theoretic security. The discrete modulated (DM) continuous variable (CV) QKD protocol

in particular

is a suitable candidate for large-scale deployment of quantum-safe communication due to its simplicity and compatibility with standard high-speed telecommunication technology. Here

we present the first experimental demonstration of a four-state DM CVQKD system

successfully generating composable finite-size keys

secure against collective attacks over a 20 km fiber channel with 2.3 × 10

coherent quantum states

achieving a positive composable key rate of 11.04 × 10

−3

bits/symbol. This accomplishment is enabled by using an advanced security proof

meticulously selecting its parameters

and the fast

stable operation of the system. Our results mark a significant step toward the large-scale deployment of practical

high-performance

cost-effective

and highly secure quantum key distribution networks using standard telecommunication components.

关键词

Keywords

references

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