Experimental demonstration of a quantum key distribution without signal disturbance monitoring


In existing quantum key distribution protocols, two legitimate peers, Alice and Bob, must monitor the signal disturbance to place a bound on the potential information leakage. However, in the round-robin differential phase shift (RRDPS) protocol, monitoring of the signal disturbance is unnecessary. Here, we present the first active implementation of the RRDPS protocol. In our experiment, Alice prepares packets of pulses, where each packet is a train with 65 pulses and the global phase of each packet is randomized. Bob uses a novel actively controlled variable-delay interferometer to realize the random switching of different delays. Benefiting from the large pulse number of each packet, and the high stability and low insertion loss of the interferometer, the system can distribute a secret key over a distance of 90 km. Our experimental demonstration and results confirm the feasibility of the RRDPS protocol, particularly in high-error situations.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Figure 1: Experimental set-up for the RRDPS QKD system.
Figure 2: Parameters of each delay of the variable-delay interferometer.
Figure 3: Numerical simulation and experimental results.
Figure 4: Secret key rates versus error rate (20 km transmission distance).


  1. 1

    Bennett, C. H. & Brassard, G. in Proceedings of the IEEE International Conference on Computers, Systems and Signal Processing 175–179 (IEEE, 1984).

  2. 2

    Stucki, D., Gisin, N., Guinnard, O., Ribordy, G. & Zbinden, H. Quantum key distribution over 67 km with a plug&play system. New J. Phys. 4, 41 (2002).

    ADS  Article  Google Scholar 

  3. 3

    Takesue, H. et al. Quantum key distribution over a 40-dB channel loss using superconducting single-photon detectors. Nature Photon. 1, 343–348 (2007).

    ADS  Article  Google Scholar 

  4. 4

    Wang, S. et al. 2 GHz clock quantum key distribution over 260 km of standard telecom fiber. Opt. Lett. 37, 1008–1010 (2012).

    ADS  Article  Google Scholar 

  5. 5

    Korzh, B. et al. Provably secure and practical quantum key distribution over 307 km of optical fibre. Nature Photon. 9, 163–168 (2015).

    ADS  Article  Google Scholar 

  6. 6

    Dixon, A., Yuan, Z., Dynes, J., Sharpe, A. & Shields, A. Gigahertz decoy quantum key distribution with 1 Mbit/s secure key rate. Opt. Express 16, 18790–18797 (2008).

    ADS  Article  Google Scholar 

  7. 7

    Dixon, A. et al. High speed prototype quantum key distribution system and long term field trial. Opt. Express 23, 7583–7592 (2015).

    ADS  Article  Google Scholar 

  8. 8

    Jouguet, P., Kunz-Jacques, S., Leverrier, A., Grangier, P. & Diamanti, E. Experimental demonstration of long-distance continuous-variable quantum key distribution. Nature Photon. 7, 378–381 (2013).

    ADS  Article  Google Scholar 

  9. 9

    Rubenok, A., Slater, J. A., Chan, P., Lucio-Martinez, I. & Tittel, W. Real-world two-photon interference and proof-of-principle quantum key distribution immune to detector attacks. Phys. Rev. Lett. 111, 130501 (2013).

    ADS  Article  Google Scholar 

  10. 10

    Tang, Z. et al. Experimental demonstration of polarization encoding measurement-device-independent quantum key distribution. Phys. Rev. Lett. 112, 190503 (2014).

    ADS  Article  Google Scholar 

  11. 11

    Peev, M. et al. The SECOQC quantum key distribution network in Vienna. New J. Phys. 11, 075001 (2009).

    ADS  Article  Google Scholar 

  12. 12

    Sasaki, M. et al. Field test of quantum key distribution in the Tokyo QKD network. Opt. Express 19, 10387–10409 (2011).

    ADS  Article  Google Scholar 

  13. 13

    Wang, S. et al. Field and long-term demonstration of a wide area quantum key distribution network. Opt. Express 22, 21739–21756 (2014).

    ADS  Article  Google Scholar 

  14. 14

    Frolich, B. et al. A quantum access network. Nature 501, 69–72 (2013).

    ADS  Article  Google Scholar 

  15. 15

    Lo, H.-K., Curty, M. & Tamaki, K. Secure quantum key distribution. Nature Photon. 8, 595–604 (2014).

    ADS  Article  Google Scholar 

  16. 16

    Gisin, N., Ribordy, G., Tittel, W. & Zbinden, H. Quantum cryptography. Rev. Mod. Phys. 74, 145–195 (2002).

    ADS  Article  Google Scholar 

  17. 17

    Scarani, V. et al. The security of practical quantum key distribution. Rev. Mod. Phys. 81, 1301–1350 (2009).

    ADS  Article  Google Scholar 

  18. 18

    Sasaki, T., Yamamoto, Y. & Koashi, M. Practical quantum key distribution protocol without monitoring signal disturbance. Nature 509, 475–478 (2014).

    ADS  Article  Google Scholar 

  19. 19

    Deutsch, D. et al. Quantum privacy amplification and the security of quantum cryptography over noisy channels. Phys. Rev. Lett. 77, 2818 (1996).

    ADS  Article  Google Scholar 

  20. 20

    Zhang, C. M. et al. Delayed error verification in quantum key distribution. Chin. Sci. Bull. 59, 2825–2828 (2014).

    Article  Google Scholar 

  21. 21

    Pawlowski, M. et al. Information causality as a physical principle. Nature 461, 1101–1104 (2009).

    ADS  Article  Google Scholar 

  22. 22

    Zhao, Y., Qi, B. & Lo, H.-K. Experimental quantum key distribution with active phase randomization. Appl. Phys. Lett. 90, 044106 (2007).

    ADS  Article  Google Scholar 

  23. 23

    Mo, X.-F., Zhu, B., Han, Z.-F., Gui, Y.-Z. & Guo, G.-C. Faraday–Michelson system for quantum cryptography. Opt. Lett. 30, 2632–2634 (2005).

    ADS  Article  Google Scholar 

  24. 24

    Ma, L. et al. 1310 nm differential-phase-shift QKD system using superconducting single-photon detectors. New J. Phys. 11, 045020 (2009).

    ADS  Article  Google Scholar 

  25. 25

    Walenta, N. et al. Sine gating detector with simple filtering for low-noise infra-red single photon detection at room temperature. J. Appl. Phys. 112, 063106 (2012).

    ADS  Article  Google Scholar 

  26. 26

    Yuan, Z., Dixon, A., Dynes, J., Sharpe, A. & Shields, A. Gigahertz quantum key distribution with InGaAs avalanche photodiodes. Appl. Phys. Lett. 92, 201104 (2008).

    ADS  Article  Google Scholar 

  27. 27

    Hwang, W.-Y. Quantum key distribution with high loss: toward global secure communication. Phys. Rev. Lett. 91, 057901 (2003).

    ADS  Article  Google Scholar 

  28. 28

    Wang, X.-B. Beating the photon-number-splitting attack in practical quantum cryptography. Phys. Rev. Lett. 94, 230503 (2005).

    ADS  Article  Google Scholar 

  29. 29

    Lo, H.-K., Ma, X. & Chen, K. Decoy state quantum key distribution. Phys. Rev. Lett. 94, 230504 (2005).

    ADS  Article  Google Scholar 

  30. 30

    Zhang, C. M. et al. Decoy-state measurement-device-independent quantum key distribution with mismatched-basis statistics. Sci. China Phys. Mech. Astron. 58, 590301 (2015).

    Article  Google Scholar 

Download references


The authors thank J.-D. Wang and J.-Z. Huang for scientific discussions. This work was supported by the National Natural Science Foundation of China (grant nos. 61475148, 61201239, 61205118 and 11304397), the National Basic Research Program of China (grant nos. 2011CBA00200 and 2011CB921200) and the Strategic Priority Research Program (B) of the Chinese Academy of Sciences (grant nos. XDB01030100 and XDB01030300).

Author information




S.W. and Z.-Q.Y. contributed equally to this work. S.W., Z.-Q.Y., W.C., G.-C.G. and Z.-F.H. conceived and designed the experiments. S.W., W.C. and X.-T.S. designed the variable-delay interferometer. S.W., D.-Y.H. and Z.Z. designed the control and detection parts of the system. Z.-Q.Y., W.C. and L.-J.Z. designed the software. All authors performed the experiments. Z.-Q.Y. and H.-W.L. performed the simulation and analysed the data. S.W., Z.-Q.Y., W.C. and Z.-F.H. wrote the paper.

Corresponding authors

Correspondence to Wei Chen or Zheng-Fu Han.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary information

Supplementary information (PDF 2211 kb)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Wang, S., Yin, Z., Chen, W. et al. Experimental demonstration of a quantum key distribution without signal disturbance monitoring. Nature Photon 9, 832–836 (2015). https://doi.org/10.1038/nphoton.2015.209

Download citation

Further reading


Nature Briefing

Sign up for the Nature Briefing newsletter for a daily update on COVID-19 science.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing