Abstract

In the past, long-distance free-space quantum communication experiments could only be implemented at night. During the daytime, the bright background sunlight prohibits quantum communication in transmission under conditions of high channel loss over long distances. Here, by choosing a working wavelength of 1,550 nm and developing free-space single-mode fibre-coupling technology and ultralow-noise upconversion single-photon detectors, we have overcome the noise due to sunlight and demonstrate free-space quantum key distribution over 53 km during the day. The total channel loss is 48 dB, which is greater than the 40 dB channel loss between the satellite and ground and between low-Earth-orbit satellites. Our system thus demonstrates the feasibility of satellite-based quantum communication in daylight. Moreover, given that our working wavelength is located in the optical telecom band, our system is naturally compatible with ground fibre networks and thus represents an essential step towards a satellite-constellation-based global quantum network.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

References

  1. 1.

    et al. Experimental free-space distribution of entangled photon pairs over 13 km: towards satellite-based global quantum communication. Phys. Rev. Lett. 94, 150501 (2005).

  2. 2.

    et al. Experimental demonstration of free-space decoy-state quantum key distribution over 144 km. Phys. Rev. Lett. 98, 010504 (2007).

  3. 3.

    et al. Experimental free-space quantum teleportation. Nat. Photon. 4, 376–381 (2010).

  4. 4.

    et al. Quantum teleportation and entanglement distribution over 100-kilometre free-space channels. Nature 488, 185–188 (2012).

  5. 5.

    et al. Quantum teleportation over 143 kilometres using active feed-forward. Nature 489, 269–273 (2012).

  6. 6.

    et al. Direct and full-scale experimental verifications towards ground-satellite quantum key distribution. Nat. Photon. 7, 387–393 (2013).

  7. 7.

    et al. Air-to-ground quantum communication. Nat. Photon. 7, 382–386 (2013).

  8. 8.

    et al. Experimental quasi-single-photon transmission from satellite to earth. Opt. Express 21, 20032–20040 (2013).

  9. 9.

    et al. Experimental satellite quantum communications. Phys. Rev. Lett. 115, 040502 (2015).

  10. 10.

    Chinese academy takes space under its wing. Science 332, 904–904 (2011).

  11. 11.

    Commercial Earth observation satellites. Int. Arch. Photogramm. Remote Sens. 31, 273–282 (1996).

  12. 12.

    , , & An operational and performance overview of the Iridium Low Earth Orbit satellite system. IEEE Commun. Surv. 2, 2–10 (1999).

  13. 13.

    Spacecraft Thermal Control Handbook: Fundamental Technologies Vol. 1 (American Institute of Aeronautics and Astronautics, 2002).

  14. 14.

    , , , & Free-Space Optical Quantum Key Distribution Using Intersatellite Links (CNES–Intersatellite Link Workshop, 2003).

  15. 15.

    , , & Intersatellite quantum communication feasibility study. Proc. SPIE 8163, 816309 (2011).

  16. 16.

    et al. Daylight quantum key distribution over 1.6 km. Phys. Rev. Lett. 84, 5652–5655 (2000).

  17. 17.

    , , & Practical free-space quantum key distribution over 10 km in daylight and at night. New J. Phys. 4, 43 (2002).

  18. 18.

    , , & Ultranarrow bandwidth spectral filtering for long-range free-space quantum key distribution at daytime. Opt. Lett. 34, 3169–3171 (2009).

  19. 19.

    et al. Improved timing resolution single-photon detectors in daytime free-space quantum key distribution with 1.25 GHz transmission rate. IEEE J. Sel. Top. Quantum Electron. 16, 1084–1090 (2010).

  20. 20.

    , , , & Free-space quantum key distribution with Rb vapor filters. Appl. Phys. Lett. 89, 191121 (2006).

  21. 21.

    et al. Free-space quantum cryptography in the H-alpha Fraunhofer window. Proc. SPIE 6304, 630417 (2006).

  22. 22.

    , , , & Daylight operation of a free space, entanglement-based quantum key distribution system. New J. Phys. 11, 045007 (2009).

  23. 23.

    et al. Background noise of satellite-to-ground quantum key distribution. New J. Phys. 7, 215 (2005).

  24. 24.

    et al. Ultralow noise up-conversion detector and spectrometer for the telecom band. Opt. Express 21, 13986–13991 (2013).

  25. 25.

    et al. Long-distance quantum teleportation assisted with free-space entanglement distribution. Chin. Phys. B 18, 3605 (2009).

  26. 26.

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

  27. 27.

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

  28. 28.

    , & Decoy state quantum key distribution. Phys. Rev. Lett. 94, 230504 (2005).

  29. 29.

    , & Practical issues in quantum-key-distribution postprocessing. Phys. Rev. A 81, 012318 (2010).

  30. 30.

    , , & Quantum cryptography with coherent states. Phys. Rev. A 51, 1863–1869 (1995).

  31. 31.

    , , & Limitations on practical quantum cryptography. Phys. Rev. Lett. 85, 1330–1333 (2000).

  32. 32.

    & Security of quantum key distribution using weak coherent states with nonrandom phases. Quantum Inform. Comput. 7, 431–458 (2007).

  33. 33.

    , & Experimental verification of fiber-coupling efficiency for satellite-to-ground atmospheric laser downlinks. Opt. Express 20, 15301–15308 (2012).

  34. 34.

    et al. Quantum-limited measurements of optical signals from a geostationary satellite. Optica 4, 611–616 (2017).

  35. 35.

    , & Measurement-device-independent quantum key distribution. Phys. Rev. Lett. 108, 130503 (2012).

  36. 36.

    & Side-channel-free quantum key distribution. Phys. Rev. Lett. 108, 130502 (2012).

  37. 37.

    et al. Teleporting an unknown quantum state via dual classical and Einstein–Podolsky–Rosen channels. Phys. Rev. Lett. 70, 1895–1899 (1993).

  38. 38.

    , , & Quantum repeaters: the role of imperfect local operations in quantum communication. Phys. Rev. Lett. 81, 5932–5935 (1998).

  39. 39.

    , & Quantum-enhanced measurements: beating the standard quantum limit. Science 306, 1330–1336 (2004).

  40. 40.

    Wideband photon counting and homodyne detection. Phys. Rev. A 32, 311–323 (1985).

  41. 41.

    et al. A quantum network of clocks. Nat. Phys. 10, 582–587 (2014).

  42. 42.

    et al. Low jitter up-conversion detectors for telecom wavelength GHz QKD. New J. Phys. 8, 32 (2006).

  43. 43.

    Composable security proof for continuous-variable quantum key distribution with coherent states. Phys. Rev. Lett. 114, 070501 (2015).

  44. 44.

    et al. Experimental demonstration of long-distance continuous-variable quantum key distribution. Nat. Photon. 7, 378–381 (2013).

Download references

Acknowledgements

The authors thank Y.-A. Chen, Y. Cao, Y. Liu and Y. Xu for discussions. This work was supported by the National Fundamental Research Program (grant no. 2013CB336800), the ‘Strategic Priority Research Program’ of the Chinese Academy of Sciences (grant no. XDA04030000), the National Natural Science Foundation of China, the Chinese Academy of Sciences and the 10000-Plan of Shandong Province (Taishan Scholars).

Author information

Author notes

    • Sheng-Kai Liao
    • , Hai-Lin Yong
    • , Chang Liu
    •  & Guo-Liang Shentu

    These authors contributed equally to this work.

Affiliations

  1. Shanghai Branch, National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Shanghai 201315, China

    • Sheng-Kai Liao
    • , Hai-Lin Yong
    • , Chang Liu
    • , Guo-Liang Shentu
    • , Dong-Dong Li
    • , Jin Lin
    • , Hui Dai
    • , Bo Li
    • , Jian-Yu Guan
    • , Wei Chen
    • , Yun-Hong Gong
    • , Yang Li
    • , Ge-Sheng Pan
    • , Wen-Zhuo Zhang
    • , Juan Yin
    • , Ji-Gang Ren
    • , Qiang Zhang
    • , Cheng-Zhi Peng
    •  & Jian-Wei Pan
  2. Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Shanghai 201315, China

    • Sheng-Kai Liao
    • , Hai-Lin Yong
    • , Chang Liu
    • , Guo-Liang Shentu
    • , Dong-Dong Li
    • , Jin Lin
    • , Hui Dai
    • , Bo Li
    • , Jian-Yu Guan
    • , Wei Chen
    • , Yun-Hong Gong
    • , Yang Li
    • , Ge-Sheng Pan
    • , Wen-Zhuo Zhang
    • , Juan Yin
    • , Ji-Gang Ren
    • , Xiang-Bin Wang
    • , Qiang Zhang
    • , Cheng-Zhi Peng
    •  & Jian-Wei Pan
  3. School of Information Science and Engineering, Ningbo University, Ningbo 315211, China

    • Shuang-Qiang Zhao
    • , Ze-Hong Lin
    •  & Wei-Yue Liu
  4. Edward L. Ginzton Laboratory, Stanford University, Stanford, California 94305, USA

    • Jason S. Pelc
    •  & M. M. Fejer
  5. Jinan Institute of Quantum Technology, Shandong Academy of Information and Communication Technology, Jinan 250101, China

    • Xiang-Bin Wang
    •  & Qiang Zhang

Authors

  1. Search for Sheng-Kai Liao in:

  2. Search for Hai-Lin Yong in:

  3. Search for Chang Liu in:

  4. Search for Guo-Liang Shentu in:

  5. Search for Dong-Dong Li in:

  6. Search for Jin Lin in:

  7. Search for Hui Dai in:

  8. Search for Shuang-Qiang Zhao in:

  9. Search for Bo Li in:

  10. Search for Jian-Yu Guan in:

  11. Search for Wei Chen in:

  12. Search for Yun-Hong Gong in:

  13. Search for Yang Li in:

  14. Search for Ze-Hong Lin in:

  15. Search for Ge-Sheng Pan in:

  16. Search for Jason S. Pelc in:

  17. Search for M. M. Fejer in:

  18. Search for Wen-Zhuo Zhang in:

  19. Search for Wei-Yue Liu in:

  20. Search for Juan Yin in:

  21. Search for Ji-Gang Ren in:

  22. Search for Xiang-Bin Wang in:

  23. Search for Qiang Zhang in:

  24. Search for Cheng-Zhi Peng in:

  25. Search for Jian-Wei Pan in:

Contributions

Q.Z., C.-Z.P. and J.-W.P. conceived and designed the experiment. S.-K.L., J.L., W.C., Y.L., Z.-H.L., C.-Z.P. and J.-W.P. designed QKD devices. H.-L.Y., C.L., D.-D.L., B.L., H.D., Y.-H.G., J.-G.R., C.-Z.P. and J.-W.P. developed the SMF coupling technique. G.-L.S., J.-Y.G., J.S.P., M.M.F. and Q.Z. implemented upconversion detectors. S.-K.L., H.-L.Y., S.-Q.Z. and W.-Y.L. designed software. X.-B.W. contributed to the decoy-state analysis. Q.Z., C.-Z.P. and J.-W.P. analysed the data and wrote the manuscript, with input from S.-K.L., H.-L.Y. and C.L. All authors contributed to the data collection, discussed the results, and reviewed the manuscript. C.-Z.P. and J.-W.P. supervised the whole project.

Competing interests

The authors declare no competing financial interests.

Corresponding authors

Correspondence to Qiang Zhang or Cheng-Zhi Peng or Jian-Wei Pan.

Supplementary information

PDF files

  1. 1.

    Supplementary information

    Supplementary information

About this article

Publication history

Received

Accepted

Published

DOI

https://doi.org/10.1038/nphoton.2017.116

Further reading