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Two-photon interference in the telecom C-band after frequency conversion of photons from remote quantum emitters

Abstract

Efficient fibre-based long-distance quantum communication via quantum repeaters relies on deterministic single-photon sources at telecom wavelengths, potentially exploiting the existing world-wide infrastructures. For upscaling the experimental complexity in quantum networking, two-photon interference (TPI) of remote non-classical emitters in the low-loss telecom bands is of utmost importance. Several experiments have been conducted regarding TPI of distinct emitters, for example, using trapped atoms1, ions2, nitrogen vacancy centres3,4, silicon vacancy centres5, organic molecules6 and semiconductor quantum dots7,8. However, the spectral range was far from the highly desirable telecom C-band. Here, we exploit quantum frequency conversion to realize TPI at 1,550 nm with single photons stemming from two remote quantum dots. We thereby prove quantum frequency conversion9,10,11 as a bridging technology and a precise and stable mechanism to erase the frequency difference between independent emitters. On resonance, a TPI visibility of 29  ± 3% has been observed, limited only by the spectral diffusion processes of the individual quantum dots12,13. The local fibre network used covers several rooms between two floors of the building. Even the addition of up to 2 km of fibre channel shows no influence on the TPI visibility, proving the photon wavepacket distortion to be negligible. Our studies pave the way to establish long-distance entanglement distribution between remote solid-state emitters including interfaces with various quantum hybrid systems14,15,16.

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Fig. 1: Frequency conversion of single photons from distinct quantum dots for remote TPI in the telecom C-band.
Fig. 2: Remote TPI measurement with QD1 and QD2.
Fig. 3: Demonstration of a local fibre network via additional fibre path length before TPI is carried out.
Fig. 4: Simulated degradation of remote TPI visibility after single-photon wavepacket distortion in telecommunication fibre.

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Data availability

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

References

  1. Beugnon, J. et al. Quantum interference between two single photons emitted by independently trapped atoms. Nature 440, 779–782 (2006).

    Article  CAS  Google Scholar 

  2. Maunz, P. et al. Quantum interference of photon pairs from two remote trapped atomic ions. Nat. Phys. 3, 538–541 (2007).

    Article  CAS  Google Scholar 

  3. Bernien, H. et al. Two-photon quantum interference from separate nitrogen vacancy centers in diamond. Phys. Rev. Lett. 108, 043604 (2012).

    Article  Google Scholar 

  4. Sipahigil, A. et al. Quantum interference of single photons from remote nitrogen-vacancy centers in diamond. Phys. Rev. Lett. 108, 143601 (2012).

    Article  CAS  Google Scholar 

  5. Sipahigil, A. et al. Indistinguishable photons from separated silicon-vacancy centers in diamond. Phys. Rev. Lett. 113, 113602 (2014).

    Article  CAS  Google Scholar 

  6. Lettow, R. et al. Quantum interference of tunably indistinguishable photons from remote organic molecules. Phys. Rev. Lett. 104, 123605 (2010).

    Article  CAS  Google Scholar 

  7. Patel, R. B. et al. Two-photon interference of the emission from electrically tunable remote quantum dots. Nat. Photon. 4, 632–635 (2010).

    Article  CAS  Google Scholar 

  8. Flagg, E. B. et al. Interference of single photons from two separate semiconductor quantum dots. Phys. Rev. Lett. 104, 137401 (2010).

    Article  Google Scholar 

  9. Zaske, S. et al. Visible-to-telecom quantum frequency conversion of light from a single quantum emitter. Phys. Rev. Lett. 109, 147404 (2012).

    Article  Google Scholar 

  10. Ates, S. et al. Two-photon interference using background-free quantum frequency conversion of single photons emitted by an InAs quantum dot. Phys. Rev. Lett. 109, 147405 (2012).

    Article  Google Scholar 

  11. Kambs, B. et al. Low-noise quantum frequency down-conversion of indistinguishable photons. Opt. Express 24, 22250 (2016).

    Article  CAS  Google Scholar 

  12. Robinson, H. D. & Goldberg, B. B. Light-induced spectral diffusion in single self-assembled quantum dots. Phys. Rev. B 61, R5086–R5089 (2000).

    Article  CAS  Google Scholar 

  13. Kuhlmann, A. V. et al. Charge noise and spin noise in a semiconductor quantum device. Nat. Phys. 9, 570–575 (2013).

    Article  CAS  Google Scholar 

  14. De Greve, K. et al. Quantum-dot spin–photon entanglement via frequency downconversion to telecom wavelength. Nature 491, 421–425 (2012).

    Article  Google Scholar 

  15. Maring, N. et al. Photonic quantum state transfer between a cold atomic gas and a crystal. Nature 551, 485–488 (2017).

    Article  CAS  Google Scholar 

  16. Bock, M. et al. High-fidelity entanglement between a trapped ion and a telecom photon via quantum frequency conversion. Nat. Commun. 9, 1998 (2018).

    Article  Google Scholar 

  17. Sangouard, N. et al. Long-distance entanglement distribution with single-photon sources. Phys. Rev. A 76, 050301 (2007).

    Article  Google Scholar 

  18. Michler, P. Quantum Dots for Quantum Information Technologies (Springer International, Cham, 2017).

  19. Loredo, J. C. et al. Scalable performance in solid-state single-photon sources. Optica 3, 433–440 (2016).

    Article  Google Scholar 

  20. Wang, H. et al. Near-transform-limited single photons from an efficient solid-state quantum emitter. Phys. Rev. Lett. 116, 213601 (2016).

    Article  Google Scholar 

  21. Lenzini, F. et al. Active demultiplexing of single photons from a solid-state source. Laser Photonics Rev. 11, 1600297 (2017).

    Article  Google Scholar 

  22. Wang, H. et al. High-efficiency multiphoton boson sampling. Nat. Photon. 11, 361–365 (2017).

    Article  CAS  Google Scholar 

  23. Yu, L. et al. Two-photon interference at telecom wavelengths for time-bin-encoded single photons from quantum-dot spin qubits. Nat. Commun. 6, 8955 (2015).

    Article  CAS  Google Scholar 

  24. Felle, M. et al. Interference with a quantum dot single-photon source and a laser at telecom wavelength. Appl. Phys. Lett. 107, 131106 (2015).

    Article  Google Scholar 

  25. Legero, T., Wilk, T., Kuhn, A. & Rempe, G. Time-resolved two-photon quantum interference. Appl. Phys. B 77, 797–802 (2003).

    Article  CAS  Google Scholar 

  26. Kambs, B. & Becher, C. Limitations on the indistinguishability of photons from remote solid state sources. Preprint at https://arxiv.org/abs/1806.08213 (2018).

  27. Weber, J. H. et al. Overcoming correlation fluctuations in two-photon interference experiments with differently bright and independently blinking remote quantum emitters. Phys. Rev. B 97, 195414 (2018).

    Article  Google Scholar 

  28. Lenhard, A. et al. Single telecom photon heralding by wavelength multiplexing in an optical fiber. Appl. Phys. B 122, 20 (2016).

    Article  Google Scholar 

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

    Article  CAS  Google Scholar 

  30. Cuevas, A. et al. Long-distance distribution of genuine energy-time entanglement. Nat. Commun. 4, 2871 (2013).

    Article  CAS  Google Scholar 

  31. Vural, H. et al. Two-photon interference in an atom–quantum dot hybrid system. Optica 5, 367 (2018).

    Article  Google Scholar 

  32. He, Y.-M. et al. On-demand semiconductor single-photon source with near-unity indistinguishability. Nat. Nanotech. 8, 213–217 (2013).

    Article  CAS  Google Scholar 

  33. Somaschi, N. et al. Near-optimal single-photon sources in the solid state. Nat. Photon. 10, 340–345 (2016).

    Article  CAS  Google Scholar 

  34. 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).

    Article  Google Scholar 

  35. Portalupi, S. L. et al. Simultaneous Faraday filtering of the Mollow triplet sidebands with the Cs-D1 clock transition. Nat. Commun. 7, 13632 (2016).

    Article  CAS  Google Scholar 

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Acknowledgements

The authors thank T. Herzog for the installation of the telecom fibre links. The authors also thank M. Bock for discussions and advice during preparation of the QFC set-ups. This work was financially supported by the Deutsche Forschungsgemeinschaft (DFG) via projects MI 500/26-1 and BE 2306/6-1, as well as by the German Federal Ministry of Science and Education (Bundesministerium für Bildung und Forschung, BMBF) within project Q.com (contract nos. 16KIS0115 and 16KIS0127). The research of IQST is supported financially by the Ministry of Science, Research and Arts Baden-Württemberg.

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Contributions

J.H.W., B.K., S.K. and S.L.P. performed the experiment with the support of J.K. B.K. built the frequency converters. M.J. provided the samples. J.H.W. and B.K. analysed the data. B.K., H.V. and J.M. set up the theoretical model. J.M. and H.V. conducted the numerical simulations. J.H.W., S.L.P. and B.K. wrote the manuscript with support from P.M. and input from all authors. P.M. and C.B. coordinated the project. All authors actively took part in all scientific discussions.

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Correspondence to Simone L. Portalupi or Peter Michler.

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Weber, J.H., Kambs, B., Kettler, J. et al. Two-photon interference in the telecom C-band after frequency conversion of photons from remote quantum emitters. Nature Nanotech 14, 23–26 (2019). https://doi.org/10.1038/s41565-018-0279-8

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