A quantum network node with crossed optical fibre cavities

Abstract

Quantum networks provide unique possibilities for resolving open questions on entanglement1 and promise innovative applications ranging from secure communication to scalable computation2. Although two quantum nodes coupled by a single channel are adequate for basic quantum communication tasks between two parties3, fully functional large-scale quantum networks require a web-like architecture with multiply connected nodes4. Efficient interfaces between network nodes and channels can be implemented with optical cavities5. Using two optical fibre cavities coupled to one atom, we here realize a quantum network node that connects to two quantum channels, one provided by each cavity. It functions as a passive, heralded and high-fidelity quantum memory that requires neither amplitude- and phase-critical control fields6,7,8 nor error-prone feedback loops9. Our node is robust, fits naturally into larger fibre-based networks and has prospects for extensions including qubit-controlled quantum switches10,11, routers12,13 and repeaters14,15.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Fig. 1: Crossed optical fibre cavities.
Fig. 2: Scheme for the heralded quantum memory.
Fig. 3: Fidelity of the heralded quantum memory.
Fig. 4: Heralded storage with variable herald cavity detuning.

Data availability

Source data for Figs. 1, 3 and 4 are provided with the paper. The data that support the findings of this study are available from the corresponding author upon reasonable request.

References

  1. 1.

    Acín, A., Cirac, J. I. & Lewenstein, M. Entanglement percolation in quantum networks. Nat. Phys. 3, 256–259 (2007).

    Article  Google Scholar 

  2. 2.

    Wehner, S., Elkouss, D. & Hanson, R. Quantum internet: a vision for the road ahead. Science 362, eaam9288 (2018).

    ADS  MathSciNet  Article  Google Scholar 

  3. 3.

    Ritter, S. et al. An elementary quantum network of single atoms in optical cavities. Nature 484, 195–200 (2012).

    ADS  Article  Google Scholar 

  4. 4.

    Kimble, H. J. The quantum internet. Nature 453, 1023–1030 (2008).

    ADS  Article  Google Scholar 

  5. 5.

    Reiserer, A. & Rempe, G. Cavity-based quantum networks with single atoms and optical photons. Rev. Mod. Phys. 87, 1379–1418 (2015).

    ADS  Article  Google Scholar 

  6. 6.

    Gorshkov, A. V., André, A., Fleischhauer, M., Sørensen, A. S. & Lukin, M. D. Universal approach to optimal photon storage in atomic media. Phys. Rev. Lett. 98, 123601 (2007).

    ADS  Article  Google Scholar 

  7. 7.

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

    ADS  Article  Google Scholar 

  8. 8.

    Körber, M. et al. Decoherence-protected memory for a single-photon qubit. Nat. Photon. 12, 18–21 (2018).

    ADS  Article  Google Scholar 

  9. 9.

    Kalb, N., Reiserer, A., Ritter, S. & Rempe, G. Heralded storage of a photonic quantum bit in a single atom. Phys. Rev. Lett. 114, 220501 (2015).

    ADS  Article  Google Scholar 

  10. 10.

    Reiserer, A., Kalb, N., Rempe, G. & Ritter, S. A quantum gate between a flying optical photon and a single trapped atom. Nature 508, 237–240 (2014).

    ADS  Article  Google Scholar 

  11. 11.

    Tiecke, T. G. et al. Nanophotonic quantum phase switch with a single atom. Nature 508, 241–244 (2014).

    ADS  Article  Google Scholar 

  12. 12.

    Shomroni, I. et al. All-optical routing of single photons by a one-atom switch controlled by a single photon. Science 345, 903–906 (2014).

    ADS  Article  Google Scholar 

  13. 13.

    Scheucher, M., Hilico, A., Will, E., Volz, J. & Rauschenbeutel, A. Quantum optical circulator controlled by a single chirally coupled atom. Science 354, 1577–1580 (2016).

    ADS  Article  Google Scholar 

  14. 14.

    Briegel, H.-J., Dür, W., Cirac, J. I. & Zoller, P. Quantum repeaters: the role of imperfect local operations in quantum communication. Phys. Rev. Lett. 81, 5932–5935 (1998).

    ADS  Article  Google Scholar 

  15. 15.

    Uphoff, M., Brekenfeld, M., Rempe, G. & Ritter, S. An integrated quantum repeater at telecom wavelength with single atoms in optical fiber cavities. Appl. Phys. B 122, 46 (2016).

    ADS  Article  Google Scholar 

  16. 16.

    Bussières, F. et al. Prospective applications of optical quantum memories. J. Mod. Opt. 60, 1519–1537 (2013).

    ADS  MathSciNet  Article  Google Scholar 

  17. 17.

    Hedges, M. P., Longdell, J. J., Li, Y. & Sellars, M. J. Efficient quantum memory for light. Nature 465, 1052–1056 (2010).

    ADS  Article  Google Scholar 

  18. 18.

    Cho, Y.-W. et al. Highly efficient optical quantum memory with long coherence time in cold atoms. Optica 3, 100–107 (2016).

    ADS  Article  Google Scholar 

  19. 19.

    Wang, Y. et al. Efficient quantum memory for single-photon polarization qubits. Nat. Photon. 13, 346–351 (2019).

    ADS  Article  Google Scholar 

  20. 20.

    Borregaard, J., Kómár, P., Kessler, E., Sørensen, A. & Lukin, M. Heralded quantum gates with integrated error detection in optical cavities. Phys. Rev. Lett. 114, 110502 (2015).

    ADS  Article  Google Scholar 

  21. 21.

    Lin, G. W., Zou, X. B., Lin, X. M. & Guo, G. C. Heralded quantum memory for single-photon polarization qubits. EPL 86, 30006 (2009).

    ADS  Article  Google Scholar 

  22. 22.

    Koshino, K., Ishizaka, S. & Nakamura, Y. Deterministic photon–photon \(\sqrt{{\rm{SWAP}}}\) gate using a Λ system. Phys. Rev. A 82, 010301 (2010).

    ADS  Article  Google Scholar 

  23. 23.

    Tanji, H., Ghosh, S., Simon, J., Bloom, B. & Vuletić, V. Heralded single-magnon quantum memory for photon polarization states. Phys. Rev. Lett. 103, 043601 (2009).

    ADS  Article  Google Scholar 

  24. 24.

    Kurz, C. et al. Experimental protocol for high-fidelity heralded photon-to-atom quantum state transfer. Nat. Commun. 5, 5527 (2014).

    ADS  Article  Google Scholar 

  25. 25.

    Yang, S. et al. High-fidelity transfer and storage of photon states in a single nuclear spin. Nat. Photon. 10, 507–511 (2016).

    ADS  Article  Google Scholar 

  26. 26.

    Delteil, A., Sun, Z., Fält, S. & Imamoğlu, A. Realization of a cascaded quantum system: heralded absorption of a single photon qubit by a single-electron charged quantum dot. Phys. Rev. Lett. 118, 177401 (2017).

    ADS  Article  Google Scholar 

  27. 27.

    Bechler, O. et al. A passive photon–atom qubit swap operation. Nat. Phys. 14, 996–1000 (2018).

    Article  Google Scholar 

  28. 28.

    Chen, Y.-A. et al. Memory-built-in quantum teleportation with photonic and atomic qubits. Nat. Phys. 4, 103–107 (2008).

    Article  Google Scholar 

  29. 29.

    Trautmann, N. & Alber, G. Dissipation-enabled efficient excitation transfer from a single photon to a single quantum emitter. Phys. Rev. A 93, 053807 (2016).

    ADS  Article  Google Scholar 

  30. 30.

    Hunger, D. et al. A fiber Fabry–Perot cavity with high finesse. New J. Phys. 12, 065038 (2010).

    ADS  Article  Google Scholar 

  31. 31.

    Uphoff, M., Brekenfeld, M., Rempe, G. & Ritter, S. Frequency splitting of polarization eigenmodes in microscopic Fabry–Perot cavities. New J. Phys. 17, 013053 (2015).

    ADS  Article  Google Scholar 

  32. 32.

    Duan, L.-M. & Kimble, H. J. Scalable photonic quantum computation through cavity-assisted interactions. Phys. Rev. Lett. 92, 127902 (2004).

    ADS  Article  Google Scholar 

  33. 33.

    Viola, L., Knill, E. & Lloyd, S. Dynamical decoupling of open quantum systems. Phys. Rev. Lett. 82, 2417–2421 (1999).

    ADS  MathSciNet  Article  Google Scholar 

  34. 34.

    Nunn, J. et al. Multimode memories in atomic ensembles. Phys. Rev. Lett. 101, 260502 (2008).

    ADS  Article  Google Scholar 

  35. 35.

    Morin, O., Körber, M., Langenfeld, S. & Rempe, G. Deterministic shaping and reshaping of single-photon temporal wave functions. Phys. Rev. Lett. 123, 133602 (2019).

    ADS  MathSciNet  Article  Google Scholar 

  36. 36.

    Radnaev, A. G. et al. A quantum memory with telecom-wavelength conversion. Nat. Phys. 6, 894–899 (2010).

    Article  Google Scholar 

  37. 37.

    Albrecht, B., Farrera, P., Fernandez-Gonzalvo, X., Cristiani, M. & de Riedmatten, H. A waveguide frequency converter connecting rubidium-based quantum memories to the telecom C-band. Nat. Commun. 5, 3376 (2014).

    ADS  Article  Google Scholar 

  38. 38.

    Meyer, H. et al. Direct photonic coupling of a semiconductor quantum dot and a trapped ion. Phys. Rev. Lett. 114, 123001 (2015).

    ADS  Article  Google Scholar 

  39. 39.

    Yoo, H. & Eberly, J. H. Dynamical theory of an atom with two or three levels interacting with quantized cavity fields. Phys. Rep. 118, 239–337 (1985).

    ADS  Article  Google Scholar 

Download references

Acknowledgements

We thank S. Ritter and M. Uphoff for contributions during an early stage of this work and T. Urban for contributions to the design and fabrication of the experimental chamber. This work was supported by the Bundesministerium für Bildung und Forschung via the Verbund Q.Link.X (grant no. 16KIS0870), the Deutsche Forschungsgemeinschaft under Germany’s Excellence Strategy (EXC-2111, 390814868) and the European Union’s Horizon 2020 research and innovation programme via the project Quantum Internet Alliance (GA no. 820445). J.D.C. acknowledges support from the Alexander von Humboldt Foundation.

Author information

Affiliations

Authors

Contributions

All authors contributed to the experiment, analysis of the results and writing of the manuscript.

Corresponding author

Correspondence to Manuel Brekenfeld.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Peer review information Nature Physics thanks Lijun Ma and the other, anonymous, reviewer(s) 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 text and Figs. 1–4.

Source data

Source Data Fig. 1

Plotted data Fig. 1.

Source Data Fig. 3

Plotted data Fig. 3.

Source Data Fig. 4

Plotted data Fig. 4.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Brekenfeld, M., Niemietz, D., Christesen, J.D. et al. A quantum network node with crossed optical fibre cavities. Nat. Phys. 16, 647–651 (2020). https://doi.org/10.1038/s41567-020-0855-3

Download citation