Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Chip-integrated visible–telecom entangled photon pair source for quantum communication

Abstract

Photon pair sources are fundamental building blocks for quantum entanglement and quantum communication. Recent studies in silicon photonics have documented promising characteristics for photon pair sources within the telecommunications band, including sub-milliwatt optical pump power, high spectral brightness and high photon purity. However, most quantum systems suitable for local operations, such as storage and computation, support optical transitions in the visible or short near-infrared bands. In comparison to telecommunications wavelengths, the higher optical attenuation in silica at such wavelengths limits the length scale over which optical-fibre-based quantum communication between such local nodes can take place. One approach to connect such systems over fibre is through a photon pair source that can bridge the visible and telecom bands, but an appropriate source, which should produce narrow-band photon pairs with a high signal-to-noise ratio, has not yet been developed in an integrated platform. Here, we demonstrate a nanophotonic visible–telecom photon pair source, using high quality factor silicon nitride resonators to generate narrow-band photon pairs with unprecedented purity and brightness, with a coincidence-to-accidental ratio up to 3,780 ± 140 and a detected photon pair flux up to (18,400 ± 1,000) pairs s−1. We further demonstrate visible–telecom time–energy entanglement and its distribution over a 20 km fibre, far exceeding the fibre length over which purely visible wavelength quantum light sources can be efficiently transmitted. Finally, we show how dispersion engineering of the microresonators enables the connections of different species of trapped atoms/ions, defect centres and quantum dots to the telecommunications bands for future quantum communication systems.

This is a preview of subscription content, access via your institution

Access options

Rent or buy this article

Prices vary by article type

from$1.95

to$39.95

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Motivation and scheme for a chip-integrated visible–telecom entangled photon pair source.
Fig. 2: Dispersion/coupling engineering essential for the chip-integrated visible–telecom photon source.
Fig. 3: Mode splitting technique is employed to identify the exact mode numbers for phase matching.
Fig. 4: Visible–telecom photon pairs are generated when both phases and frequencies are matched.
Fig. 5: Characterizations show state-of-the-art performance for power efficiency and photon purity.
Fig. 6: Visible–telecom time–energy entanglement is generated and then distributed over distance.

Similar content being viewed by others

Data availability

The data that supports the plots within this paper and other findings of this study are available from the corresponding authors upon reasonable request.

References

  1. Gisin, N. & Thew, R. Quantum communication. Nat. Photon. 1, 165–171 (2007).

    Article  ADS  Google Scholar 

  2. Lvovsky, A. I., Sanders, B. C. & Tittel, W. Optical quantum memory. Nat. Photon. 3, 706–714 (2009).

    Article  ADS  Google Scholar 

  3. Simon, C. et al. Quantum memories: A review based on the European integrated project Qubit Applications (QAP). Euro. Phys. J. D 58, 1–22 (2010).

    Article  ADS  Google Scholar 

  4. Miya, T., Terunuma, Y., Hosaka, T. & Miyashita, T. Ultimate low-loss single-mode fibre at 1.55 μm. Electron. Lett. 15, 106–108 (1979).

    Article  ADS  Google Scholar 

  5. Raymer, M. G. & Srinivasan, K. Manipulating the color and shape of single photons. Phys. Today 65, 32–37 (2012).

    Article  Google Scholar 

  6. Pan, J.-W., Bouwmeester, D., Weinfurter, H. & Zeilinger, A. Experimental entanglement swapping: entangling photons that never interacted. Phys. Rev. Lett. 80, 3891–3894 (1998).

    Article  ADS  MathSciNet  Google Scholar 

  7. Halder, M. et al. Entangling independent photons by time measurement. Nat. Phys. 3, 692–695 (2007).

    Article  Google Scholar 

  8. Hensen, B. et al. Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres. Nature 526, 682–686 (2015).

    Article  ADS  Google Scholar 

  9. Clausen, C. et al. A source of polarization-entangled photon pairs interfacing quantum memories with telecom photons. New J. Phys. 16, 093058 (2014).

    Article  ADS  Google Scholar 

  10. Söller, C. et al. Bridging visible and telecom wavelengths with a single-mode broadband photon pair source. Phys. Rev. A. 81, 031801 (2010).

    Article  ADS  Google Scholar 

  11. Schunk, G. et al. Interfacing transitions of different alkali atoms and telecom bands using one narrowband photon pair source. Optica 2, 773–778 (2015).

    Article  Google Scholar 

  12. Fekete, J., Rieländer, D., Cristiani, M. & de Riedmatten, H. Ultranarrow-band photon-pair source compatible with solid state quantum memories and telecommunication networks. Phys. Rev. Lett. 110, 220502 (2013).

    Article  ADS  Google Scholar 

  13. Slattery, O., Ma, L., Kuo, P. & Tang, X. Narrow-linewidth source of greatly non-degenerate photon pairs for quantum repeaters from a short singly resonant cavity. Appl. Phys. B 121, 413–419 (2015).

    Article  ADS  Google Scholar 

  14. Rieländer, D., Lenhard, A., Mazzera, M. & de Riedmatten, H. Cavity enhanced telecom heralded single photons for spin-wave solid state quantum memories. New J. Phys. 18, 123013 (2016).

  15. Caspani, L. et al. Integrated sources of photon quantum states based on nonlinear optics. Light: Sci. Appl. 6, e17100 (2017).

    Article  Google Scholar 

  16. Jiang, W. C., Lu, X., Zhang, J., Painter, O. & Lin, Q. Silicon-chip source of bright photon pairs. Opt. Express 23, 20884–20904 (2015).

    Article  ADS  Google Scholar 

  17. Lu, X., Jiang, W. C., Zhang, J. & Lin, Q. Biphoton statistics of quantum light generated on a silicon chip. ACS Photon. 3, 1626–1636 (2016).

    Article  Google Scholar 

  18. Grassani, D. et al. Micrometer-scale integrated silicon source of time–energy entangled photons. Optica 2, 88–94 (2015).

    Article  Google Scholar 

  19. Savanier, M., Kumar, R. & Mookherjea, S. Photon pair generation from compact silicon microring resonators using microwatt-level pump powers. Opt. Express 24, 3313–3328 (2016).

    Article  ADS  Google Scholar 

  20. Ramelow, S. et al. Silicon-nitride platform for narrowband entangled photon generation. Preprint at https://arXiv.org:/abs/1508.04358 (2015).

  21. Jaramillo-Villegas, J. A. et al. Persistent energy–time entanglement covering multiple resonances of an on-chip biphoton frequency comb. Optica 4, 655–658 (2017).

    Article  Google Scholar 

  22. Wang, J. et al. Multidimensional quantum entanglement with large-scale integrated optics. Science 360, 285–291 (2018).

    Article  ADS  MathSciNet  Google Scholar 

  23. Okawachi, Y. et al. Octave-spanning frequency comb generation in a silicon nitride chip. Opt. Lett. 36, 3398–3400 (2011).

    Article  ADS  Google Scholar 

  24. Li, Q. et al. Stably accessing octave-spanning microresonator frequency combs in the soliton regime. Optica 4, 193–203 (2017).

    Article  Google Scholar 

  25. Karpov, M., Pfeiffer, M. H. P., Liu, J., Lukashchuk, A. & Kippenberg, T. J. Photonic chip-based soliton frequency combs covering the biological imaging window. Nat. Commun. 9, 1146 (2018).

    Article  ADS  Google Scholar 

  26. Kues, M. et al. On-chip generation of high-dimensional entangled quantum states and their coherent control. Nature 546, 622–626 (2017).

    Article  ADS  Google Scholar 

  27. Imany, P. et al. 50-GHz-spaced comb of high-dimensional frequency-bin entangled photons from an on-chip silicon nitride microresonator. Opt. Express 26, 1825–1840 (2018).

    Article  ADS  Google Scholar 

  28. Li, Q., Davanço, M. & Srinivasan, K. Efficient and low-noise single-photon-level frequency conversion interfaces using silicon nanophotonics. Nat. Photon. 10, 406–414 (2016).

    Article  ADS  Google Scholar 

  29. Boyd, R. W. Nonlinear Optics (Academic Press, Amsterdam, 2008).

  30. Agrawal, G. P. Nonlinear Fiber Optics (Academic Press, Amsterdam, 2007).

  31. Shah Hosseini, E., Yegnanarayanan, S., Atabaki, A. H., Soltani, M. & Adibi, A. Systematic design and fabrication of high-Q single-mode pulley-coupled planar silicon nitride microdisk resonators at visible wavelengths. Opt. Express 18, 2127–2136 (2010).

    Article  ADS  Google Scholar 

  32. Lu, X., Rogers, S., Jiang, W. C. & Lin, Q. Selective engineering of cavity resonance for frequency matching in optical parametric processes. Appl. Phys. Lett. 105, 151104 (2014).

    Article  ADS  Google Scholar 

  33. Inagaki, T., Matsuda, N., Tadanaga, O., Asobe, M. & Takesue, H. Entanglement distribution over 300 km of fiber. Opt. Express 21, 23241–23249 (2013).

    Article  ADS  Google Scholar 

  34. Sun, Q.-C. et al. Entanglement swapping over 100 km optical fiber with independent entangled photon-pair sources. Optica 4, 1214–1218 (2017).

    Article  Google Scholar 

  35. Coimbatore Balram, K. et al. The nanolithography toolbox. J. Res. Natl Inst. Stand. Technol. 121, 464–475 (2016).

    Article  Google Scholar 

Download references

Acknowledgements

X.L., Q.L., G.M. and A.S. acknowledge support under the Cooperative Research Agreement between the University of Maryland and NIST-CNST, award number 70NANB10H193.

Author information

Authors and Affiliations

Authors

Contributions

X.L. led the design, fabrication and measurement of the entangled photon pair source devices. Q.L., A.S., G.M. and K.S. provided assistance with design and measurement. D.A.W. provided assistance with fabrication and V.A. contributed experimental tools. X.L. and K.S. wrote the manuscript. K.S. supervised the project.

Corresponding authors

Correspondence to Xiyuan Lu or Kartik Srinivasan.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Journal peer review information: Nature Physics thanks Anthony Laing and other anonymous reviewers for their contribution to the peer review of this work.

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Sections 1–4 and Supplementary Figures 1–4.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Lu, X., Li, Q., Westly, D.A. et al. Chip-integrated visible–telecom entangled photon pair source for quantum communication. Nat. Phys. 15, 373–381 (2019). https://doi.org/10.1038/s41567-018-0394-3

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41567-018-0394-3

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

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