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Experimental entanglement of six photons in graph states

Nature Physics volume 3, pages 9195 (2007) | Download Citation

Abstract

Graph states1,2,3—multipartite entangled states that can be represented by mathematical graphs—are important resources for quantum computation4, quantum error correction3, studies of multiparticle entanglement1 and fundamental tests of non-locality5,6,7 and decoherence8. Here, we demonstrate the experimental entanglement of six photons and engineering of multiqubit graph states9,10,11. We have created two important examples of graph states, a six-photon Greenberger–Horne–Zeilinger state5, the largest photonic Schrödinger cat so far, and a six-photon cluster state2, a state-of-the-art ‘one-way quantum computer’4. With small modifications, our method allows us, in principle, to create various further graph states, and therefore could open the way to experimental tests of, for example, quantum algorithms4,12 or loss- and fault-tolerant one-way quantum computation13,14.

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Acknowledgements

We thank H. J. Briegel, D. Browne, L.-M. Duan, T. Rudolph and S. Yu for helpful discussions. This work was supported by the National Natural Science Foundation of China, the Chinese Academy of Sciences. This work was also supported by the Alexander von Humboldt Foundation, the Marie Curie Excellence Grant of the EU, the FWF, the DFG and EU (Scala, Olaqui, Prosecco, QICS, Quprodis).

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Affiliations

  1. Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China

    • Chao-Yang Lu
    • , Xiao-Qi Zhou
    • , Wei-Bo Gao
    • , Jin Zhang
    • , Zhen-Sheng Yuan
    • , Tao Yang
    •  & Jian-Wei Pan
  2. Institut für Quantenoptik und Quanteninformation, Österreichische Akademie der Wissenschaften, Technikerstraße 21A, A-6020 Innsbruck, Austria

    • Otfried Gühne
  3. Physikalisches Institut, Universität Heidelberg, Philosophenweg 12, D-69120 Heidelberg, Germany

    • Alexander Goebel
    •  & Jian-Wei Pan

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The authors declare no competing financial interests.

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Correspondence to Chao-Yang Lu or Jian-Wei Pan.

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https://doi.org/10.1038/nphys507

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