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Experimental realization of freely propagating teleported qubits


Quantum teleportation1 is central to quantum communication, and plays an important role in a number of quantum computation protocols2,3. Most information-processing applications of quantum teleportation include the subsequent manipulation of the qubit (the teleported photon), so it is highly desirable to have a teleportation procedure resulting in high-quality, freely flying qubits. In our previous teleportation experiment4, the teleported qubit had to be detected (and thus destroyed) to verify the success of the procedure. Here we report a teleportation experiment that results in freely propagating individual qubits. The basic idea is to suppress unwanted coincidence detection events by providing the photon to be teleported much less frequently than the auxiliary entangled pair. Therefore, a case of successful teleportation can be identified with high probability without the need actually to detect the teleported photon. The experimental fidelity of our procedure surpasses the theoretical limit required for the implementation of quantum repeaters5,6.

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  1. 1

    Bennett, C. H. et al. Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channels. Phys. Rev. Lett. 83, 3081–3084 (1993)

  2. 2

    Gottesman, D. & Chuang, I. L. Demonstrating the viability of universal quantum computation using teleportation and single-qubit operations. Nature 402, 390–393 (1999)

  3. 3

    Knill, E., Laflamme, R. & Milburn, G. J. A scheme for efficient quantum computation with linear optics. Nature 409, 46–52 (2001)

  4. 4

    Bouwmeester, D. et al. Experimental quantum teleportation. Nature 390, 575–579 (1997)

  5. 5

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

  6. 6

    Aschauer, H. & Briegel, H. J. Private entanglement over arbitrary distances, even using noisy apparatus. Phys. Rev. Lett. 88, 047902 (2002)

  7. 7

    Braunstein, S. L. & Kimble, H. J. A posteriori teleportation. Nature 394, 840–841 (1998)

  8. 8

    Bouwmeester, D. et al. Reply to “A posteriori teleportation”. Nature 394, 841 (1998)

  9. 9

    Kok, P. & Braunstein, S. L. Postselected versus nonpostselected quantum teleportation using parametric down-conversion. Phys. Rev. A 61, 042304 (2000)

  10. 10

    Furusawa, A. et al. Unconditional quantum teleportation. Science 282, 706–709 (1998)

  11. 11

    Kim, Y. H., Kulik, S. P. & Shih, Y. H. Quantum teleportation of a polarization state with a complete Bell state measurement. Phys. Rev. Lett. 86, 1370–1373 (2001)

  12. 12

    Grosshans, F. & Grangier, P. Quantum cloning and teleportation criteria for continuous quantum variables. Phys. Rev. A 64, R010301 (2001)

  13. 13

    Rudolph, T. & Sanders, B. C. Requirement of optical coherence for continuous variable quantum teleportation. Phys. Rev. Lett. 88, 077903 (2001)

  14. 14

    Pan, J.-W. et al. Experimental demonstration of four-photon entanglement and high-fidelity teleportation. Phys. Rev. Lett. 86, 4435–4438 (2001)

  15. 15

    Pan, J.-W. & Zeilinger, A. Greenberger-Horne-Zeilinger-state analyzer. Phys. Rev. A 57, 2208–2211 (1998)

  16. 16

    Jennewein, T., Weihs, G., Pan, J.-W. & Zeilinger, A. Experimental nonlocality proof of quantum teleportation and entanglement swapping. Phys. Rev. Lett. 88, 017093 (2002)

  17. 17

    Kurtsiefer, C., Oberparleiter, M. & Weinfurter, H. High-efficiency entangled photon pair collection in type-II parametric fluorescence. Phys. Rev. A 64, 023802 (2001)

  18. 18

    Howell, J. C., Lamas-Linares, A. & Bouwmeester, D. Experimental violation of a spin-1 Bell inequality using maximally entangled four-photon states. Phys. Rev. Lett. 88, 030401 (2002)

  19. 19

    Bennett, C. H. et al. Purification of noisy entanglement, and faithful teleportation via noisy channel. Phys. Rev. Lett. 76, 1895–1898 (1996)

  20. 20

    Pan, J.-W., Simon, C., Brukner, C. & Zeilinger, A. Entanglement purification for quantum communication. Nature 410, 1067–1070 (2001)

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This work was supported by the Austrian Science Foundation (FWF), the TMR and the QuComm programmes of the European Commission and the Alexander von Humboldt Foundation.

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Competing interests

The authors declare that they have no competing financial interests.

Correspondence to Jian-Wei Pan.

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Further reading

Figure 1: Diagrams showing the principles of the Innsbruck experiment and of achieving free propagation of teleported qubits.
Figure 2: Set-up for experimental demonstration of free propagation of teleported qubits.
Figure 3: Two typical experimental results for 45° teleportation.
Figure 4: Conditional fidelities and non-conditional fidelities obtained in 45° teleportation for different neutral filters.


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