Broadband single-photon-level memory in a hollow-core photonic crystal fibre


Storing information encoded in light is critical for realizing optical buffers for all-optical signal processing1,2 and quantum memories for quantum information processing3,4. These proposals require efficient interaction between atoms and a well-defined optical mode. Photonic crystal fibres can enhance light–matter interactions and have engendered a broad range of nonlinear effects5; however, the storage of light has proven elusive. Here, we report the first demonstration of an optical memory in a hollow-core photonic crystal fibre. We store gigahertz-bandwidth light in the hyperfine coherence of caesium atoms at room temperature using a far-detuned Raman interaction. We demonstrate a signal-to-noise ratio of 2.6:1 at the single-photon level and a memory efficiency of 27 ± 1%. Our results demonstrate the potential of a room-temperature fibre-integrated optical memory for implementing local nodes of quantum information networks.

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Figure 1: Raman quantum memory in kagome hollow-core fibre.
Figure 2: Storage of classical light in a kagome hollow-core fibre.
Figure 3: Storage of single-photon-level pulses.
Figure 4: Lifetime of memory in hollow-core fibre.


  1. 1

    Ramaswami, R., Sivarajan, K. & Sasaki, G. Optical Networks: A Practical Perspective (Morgan Kaufmann, 2009).

    Google Scholar 

  2. 2

    Zhu, Z., Gauthier, D. J. & Boyd, R. W. Stored light in an optical fiber via stimulated Brillouin scattering. Science 318, 1748–1750 (2007).

    ADS  Article  Google Scholar 

  3. 3

    Sangouard, N., Simon, C., de Riedmatten, H. & Gisin, N. Quantum repeaters based on atomic ensembles and linear optics. Rev. Mod. Phys. 83, 33–80 (2011).

    ADS  Article  Google Scholar 

  4. 4

    Lukin, M. D. Trapping and manipulating photon states in atomic ensembles. Rev. Mod. Phys. 75, 457–472 (2003).

    ADS  Article  Google Scholar 

  5. 5

    Russell, P. S. Photonic-crystal fibers. J. Lightwave Technol. 24, 4729–4749 (2006).

    ADS  Article  Google Scholar 

  6. 6

    Aspuru-Guzik, A. & Walther, P. Photonic quantum simulators. Nature Phys. 8, 285–291 (2012).

    ADS  Article  Google Scholar 

  7. 7

    Giovannetti, V., Lloyd, S. & Maccone, L. Advances in quantum metrology. Nature Photon. 5, 222–229 (2011).

    ADS  Article  Google Scholar 

  8. 8

    Pan, J.-W. et al. Multiphoton entanglement and interferometry. Rev. Mod. Phys. 84, 777–838 (2012).

    ADS  Article  Google Scholar 

  9. 9

    Nunn, J. et al. Enhancing multiphoton rates with quantum memories. Phys. Rev. Lett. 110, 133601 (2013).

    ADS  Article  Google Scholar 

  10. 10

    Specht, H. P. et al. A single-atom quantum memory. Nature 473, 190–193 (2011).

    ADS  Article  Google Scholar 

  11. 11

    Julsgaard, B., Sherson, J., Cirac, J. I., Fiurasek, J. & Polzik, E. S. Experimental demonstration of quantum memory for light. Nature 432, 482–486 (2004).

    ADS  Article  Google Scholar 

  12. 12

    Choi, K. S., Deng, H., Laurat, J. & Kimble, H. J. Mapping photonic entanglement into and out of a quantum memory. Nature 452, 67–71 (2008).

    ADS  Article  Google Scholar 

  13. 13

    Wu, B. et al. Slow light on a chip via atomic quantum state control. Nature Photon. 4, 776–779 (2010).

    ADS  Article  Google Scholar 

  14. 14

    Spillane, S. et al. Observation of nonlinear optical interactions of ultralow levels of light in a tapered optical nanofiber embedded in a hot rubidium vapor. Phys. Rev. Lett. 100, 233602 (2008).

    ADS  Article  Google Scholar 

  15. 15

    Cregan, R. F. et al. Single-mode photonic band gap guidance of light in air. Science 285, 1537–1539 (1999).

    Article  Google Scholar 

  16. 16

    Venkataraman, V., Saha, K. & Gaeta, A. L. Phase modulation at the few-photon level for weak-nonlinearity-based quantum computing. Nature Photon. 7, 138–141 (2013).

    ADS  Article  Google Scholar 

  17. 17

    Ghosh, S. et al. Low-light-level optical interactions with rubidium vapor in a photonic band-gap fiber. Phys. Rev. Lett. 97, 023603 (2006).

    ADS  Article  Google Scholar 

  18. 18

    Londero, P., Venkataraman, V., Bhagwat, A. R., Slepkov, A. D. & Gaeta, A. L. Ultralow-power four-wave mixing with Rb in a hollow-core photonic band-gap fiber. Phys. Rev. Lett. 103, 043602 (2009).

    ADS  Article  Google Scholar 

  19. 19

    Sprague, M. R. et al. Efficient optical pumping and high optical depth in a hollow-core photonic-crystal fibre for a broadband quantum memory. New J. Phys. 15, 055013 (2013).

    ADS  Article  Google Scholar 

  20. 20

    Perrella, C., Light, P. S., Stace, T. M., Benabid, F. & Luiten, A. N. High-resolution optical spectroscopy in a hollow-core photonic crystal fiber. Phys. Rev. A 85, 012518 (2012).

    ADS  Article  Google Scholar 

  21. 21

    Nunn, J. et al. Mapping broadband single-photon wave packets into an atomic memory. Phys. Rev. A 75, 011401 (2007).

    ADS  Article  Google Scholar 

  22. 22

    Reim, K. F. et al. Towards high-speed optical quantum memories. Nature Photon. 4, 218–221 (2010).

    ADS  Article  Google Scholar 

  23. 23

    Reim, K. F. et al. Single-photon-level quantum memory at room temperature. Phys. Rev. Lett. 107, 053603 (2011).

    ADS  Article  Google Scholar 

  24. 24

    Benabid, F. & Roberts, P. Linear and nonlinear optical properties of hollow core photonic crystal fiber. J. Mod. Opt. 58, 87–124 (2011).

    ADS  Article  Google Scholar 

  25. 25

    Slepkov, A. D., Bhagwat, A. R., Venkataraman, V., Londero, P. & Gaeta, A. L. Generation of large alkali vapor densities inside bare hollow-core photonic band-gap fibers. Opt. Express 16, 18976–18983 (2008).

    ADS  Article  Google Scholar 

  26. 26

    Wang, X., Zhu, T., Chen, L. & Bao, X. Tunable Fabry-Perot filter using hollow-core photonic bandgap fiber and micro-fiber for a narrow-linewidth laser. Opt. Express 19, 9617–9625 (2011).

    ADS  Article  Google Scholar 

  27. 27

    Krapick, S. et al. An efficient integrated two-color source for heralded single photons. New J. Phys. 15, 033010 (2013).

    ADS  Article  Google Scholar 

  28. 28

    Bradley, T., McFerran, J. J., Jouin, J., Thomas, P. & Benabid, F. in OSA Technical Digest, CM3I.2 (Optical Society of America, 2013).

    Google Scholar 

  29. 29

    Fernandez-Gonzalvo, X. et al. Quantum frequency conversion of quantum memory compatible photons to telecommunication wavelengths. Opt. Express 21, 19473–19487 (2013).

    ADS  Article  Google Scholar 

  30. 30

    Benabid, F., Couny, F., Knight, J. C., Birks, T. A. & Russell, P. S. J. Compact, stable and efficient all-fibre gas cells using hollow-core photonic crystal fibres. Nature 434, 488–491 (2005).

    ADS  Article  Google Scholar 

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The authors thank D. Saunders for comments on the manuscript. The work was supported by the Engineering and Physical Sciences Research Council (EPSRC; EP/J000051/1), the Quantum Interfaces, Sensors, and Communication based on Entanglement Integrating Project (EU IP Q-ESSENCE; 248095), the Air Force Office of Scientific Research: European Office of Aerospace Research & Development (AFOSR EOARD; FA8655-09-1-3020), EU IP SIQS (600645), the Royal Society, the Clarendon Fund (to M.R.S.), St Edmund Hall (to M.R.S.), EU ITN FASTQUAST (to P.S.M.), and an EU Marie-Curie Fellowship (PIIF-GA-2011-300820 to X.-M.J.; PIEF-GA-2012-331859 to W.S.K.).

Author information




M.R.S. designed the experiment and built it with assistance from D.G.E., P.S.M., W.S.K. and T.F.M.C. A.A. and P.St.J.R. designed and drew the fibre and provided valuable insights. M.R.S. collected and analysed the data. J.N. and M.R.S. performed the comparison to theory. The project was conceived by M.R.S., J.N., X.M.J. and I.A.W. M.R.S. wrote the manuscript with input from all authors.

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Correspondence to M. R. Sprague.

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The authors declare no competing financial interests.

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Sprague, M., Michelberger, P., Champion, T. et al. Broadband single-photon-level memory in a hollow-core photonic crystal fibre. Nature Photon 8, 287–291 (2014).

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