Abstract
Entanglement is the fundamental characteristic of quantum physics—much experimental effort is devoted to harnessing it between various physical systems. In particular, entanglement between light and material systems is interesting owing to their anticipated respective roles as ‘flying’ and stationary qubits in quantum information technologies (such as quantum repeaters1,2,3 and quantum networks4). Here we report the demonstration of entanglement between a photon at a telecommunication wavelength (1,338 nm) and a single collective atomic excitation stored in a crystal. One photon from an energy–time entangled pair5 is mapped onto the crystal and then released into a well-defined spatial mode after a predetermined storage time. The other (telecommunication wavelength) photon is sent directly through a 50-metre fibre link to an analyser. Successful storage of entanglement in the crystal is proved by a violation of the Clauser–Horne–Shimony–Holt inequality6 by almost three standard deviations (S = 2.64 ± 0.23). These results represent an important step towards quantum communication technologies based on solid-state devices. In particular, our resources pave the way for building multiplexed quantum repeaters7 for long-distance quantum networks.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
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)
Duan, L.-M., Lukin, M. D., Cirac, J. I. & Zoller, P. Long-distance quantum communication with atomic ensembles and linear optics. Nature 414, 413–418 (2001)
Sangouard, N., Simon, C., de Riedmatten, H. & Gisin, N. Quantum repeaters based on atomic ensembles and linear optics. Preprint at 〈http://arxiv.org/abs/0906.2699〉 (2009)
Kimble, H. J. The quantum internet. Nature 453, 1023–1030 (2008)
Franson, J. D. Bell inequality for position and time. Phys. Rev. Lett. 62, 2205–2208 (1989)
Clauser, J. F., Horne, M. A., Shimony, A. & Holt, R. A. Proposed experiment to test local hidden-variable theories. Phys. Rev. Lett. 23, 880–884 (1969)
Simon, C. et al. Quantum repeaters with photon pair sources and multimode memories. Phys. Rev. Lett. 98, 190503 (2007)
Blinov, B. B., Moehring, D., Duan, L.-M. & Monroe, C. Observation of entanglement between a single trapped ion and a single photon. Nature 428, 153–157 (2004)
Volz, J. et al. Observation of entanglement of a single photon with a trapped atom. Phys. Rev. Lett. 96, 030404 (2006)
Matsukevich, D. N. et al. Entanglement of a photon and a collective atomic excitation. Phys. Rev. Lett. 95, 040405 (2005)
de Riedmatten, H. et al. Direct measurement of decoherence for entanglement between a photon and stored atomic excitation. Phys. Rev. Lett. 97, 113603 (2006)
Chen, S. et al. Demonstration of a stable atom-photon entanglement source for quantum repeaters. Phys. Rev. Lett. 99, 180505 (2007)
Sherson, J. F. et al. Quantum teleportation between light and matter. Nature 443, 557–560 (2006)
Akiba, K., Kashiwagi, K., Arikawa, M. & Kozuma, M. Storage and retrieval of nonclassical photon pairs and conditional single photons generated by the parametric down-conversion process. N. J. Phys. 11, 013049 (2009)
Jin, X.-M. et al. Quantum interface between frequency-uncorrelated down-converted entanglement and atomic-ensemble quantum memory. Preprint at 〈http://arxiv.org/abs/1004.4691〉 (2010)
Togan, E. et al. Quantum entanglement between an optical photon and a solid-state spin qubit. Nature 466, 730–734 (2010)
Tittel, W. et al. Photon-echo quantum memory in solid state systems. Laser Photon. Rev. 4, 244–267 (2010)
Longdell, J. J., Fraval, E., Sellars, M. J. & Manson, N. B. Stopped light with storage times greater than one second using electromagnetically induced transparency in a solid. Phys. Rev. Lett. 95, 063601 (2005)
Hedges, M. P., Longdell, J. J., Li, Y. & Sellars, M. J. Efficient quantum memory for light. Nature 465, 1052–1056 (2010)
de Riedmatten, H., Afzelius, M., Staudt, M. U., Simon, C. & Gisin, N. A solid-state light-matter interface at the single-photon level. Nature 456, 773–777 (2008)
Chanelière, T., Ruggiero, J., Bonarota, M., Afzelius, M. & Gouët, J.-L. L. Efficient light storage in a crystal using an atomic frequency comb. N. J. Phys. 12, 023025 (2010)
Sabooni, M. et al. Storage and recall of weak coherent optical pulses with an efficiency of 25%. Phys. Rev. Lett. 105, 060501 (2010)
Usmani, I., Afzelius, M., de Riedmatten, H. & Gisin, N. Mapping multiple photonic qubits into and out of one solid-state atomic ensemble. Nature Commun. 1, 12 (2010)
Afzelius, M., Simon, C., de Riedmatten, H. & Gisin, N. Multimode quantum memory based on atomic frequency combs. Phys. Rev. A 79, 052329 (2009)
Kuzmich, A. et al. Generation of nonclassical photon pairs for scalable quantum communication with atomic ensembles. Nature 423, 731–734 (2003)
Afzelius, M. et al. Demonstration of atomic frequency comb memory for light with spin-wave storage. Phys. Rev. Lett. 104, 040503 (2010)
Afzelius, M. & Simon, C. Impedance-matched cavity quantum memory. Phys. Rev. A 82, 022310 (2010)
Moiseev, S. A., Andrianov, S. N. & Gubaidullin, F. F. Efficient multimode quantum memory based on photon echo in an optimal QED cavity. Phys. Rev. A 82, 022311 (2010)
Saglamyurek, E. et al. Broadband waveguide quantum memory for entangled photons. Nature 10.1038/nature09719 (this issue)
Acknowledgements
We thank R. Locher for help during the early stages of the experiment. We are grateful to A. Beveratos and W. Tittel for lending us avalanche photodiodes. This work was supported by the Swiss NCCR Quantum Photonics, the Science and Technology Cooperation Program Switzerland–Russia, as well as by the European projects QuRep and ERC-Qore. F.B. was supported in part by FQRNT.
Author information
Authors and Affiliations
Contributions
All authors contributed extensively to the work presented in this paper.
Corresponding author
Ethics declarations
Competing interests
The authors declare no competing financial interests.
Supplementary information
Supplementary Information
The file contains Supplementary Text, Supplementary Figures 1-3 with legends and additional references. (PDF 249 kb)
Rights and permissions
About this article
Cite this article
Clausen, C., Usmani, I., Bussières, F. et al. Quantum storage of photonic entanglement in a crystal. Nature 469, 508–511 (2011). https://doi.org/10.1038/nature09662
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/nature09662
This article is cited by
-
Quantum storage of entangled photons at telecom wavelengths in a crystal
Nature Communications (2023)
-
Rare-earth quantum memories: The experimental status quo
Frontiers of Physics (2023)
-
Integrated photonic platforms for quantum technology: a review
ISSS Journal of Micro and Smart Systems (2023)
-
Extending the time of coherent optical response in ensemble of singly-charged InGaAs quantum dots
Communications Physics (2022)
-
Towards entanglement distillation between atomic ensembles using high-fidelity spin operations
Communications Physics (2022)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.