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Entangled mechanical oscillators

Nature volume 459, pages 683–685 (2009)Cite this article

Abstract

Hallmarks of quantum mechanics include superposition and entanglement. In the context of large complex systems, these features should lead to situations as envisaged in the ‘Schrödinger’s cat’1 thought experiment (where the cat exists in a superposition of alive and dead states entangled with a radioactive nucleus). Such situations are not observed in nature. This may be simply due to our inability to sufficiently isolate the system of interest from the surrounding environment2,3—a technical limitation. Another possibility is some as-yet-undiscovered mechanism that prevents the formation of macroscopic entangled states4. Such a limitation might depend on the number of elementary constituents in the system5 or on the types of degrees of freedom that are entangled. Tests of the latter possibility have been made with photons, atoms and condensed matter devices6,7. One system ubiquitous to nature where entanglement has not been previously demonstrated consists of distinct mechanical oscillators. Here we demonstrate deterministic entanglement of separated mechanical oscillators, consisting of the vibrational states of two pairs of atomic ions held in different locations. We also demonstrate entanglement of the internal states of an atomic ion with a distant mechanical oscillator. These results show quantum entanglement in a degree of freedom that pervades the classical world. Such experiments may lead to the generation of entangled states of larger-scale mechanical oscillators8,9,10, and offer possibilities for testing non-locality with mesoscopic systems11. In addition, the control developed here is an important ingredient for scaling-up quantum information processing with trapped atomic ions12,13,14.

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Figure 1: Mechanical oscillators.
Figure 2: Creation of entangled mechanical oscillators.
Figure 3: Entanglement demonstration through parity oscillation.

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References

  1. Schrödinger, E. Die gegenwärtige Situation in der Quantenmechanik. Naturwissenschaften 23, 807–812,–823–828, 844–849 (1935)

    Article  ADS  Google Scholar 

  2. Ball, P. Quantum all the way. Nature 453, 22–25 (2008)

    Article  CAS  Google Scholar 

  3. Schlosshauer, M. Lifting the fog from the north. Nature 453, 39 (2008)

    Article  ADS  CAS  Google Scholar 

  4. Bassi, A. & Ghirardi, G. Dynamical reduction models. Phys. Rep. 379, 257–426 (2003)

    Article  ADS  MathSciNet  CAS  Google Scholar 

  5. Leggett, A. J. Testing the limits of quantum mechanics: Motivation, state of play, prospects. J. Phys. Condens. Matter 14, R415–R451 (2002)

    Article  ADS  CAS  Google Scholar 

  6. Aspelmeyer, M. & Zeilinger, A. A quantum renaissance. Phys. World 7, 22–28 (2008)

    Article  Google Scholar 

  7. Southwell, K. (ed.) Quantum coherence. Nature 453, 1003–1049 (2008)

    Article  ADS  CAS  Google Scholar 

  8. Mancini, S., Giovannetti, V., Vitali, D. & Tombesi, P. Entangling macroscopic oscillators exploiting radiation pressure. Phys. Rev. Lett. 88, 120401 (2002)

    Article  ADS  Google Scholar 

  9. Schwab, K. C. & Rourkes, M. L. Putting mechanics into quantum mechanics. Phys. Today 58, 36–42 (2005)

    Article  Google Scholar 

  10. Kippenberg, T. J. & Vahala, K. J. Cavity optomechanics: Back-action at the mesoscale. Science 321, 1172–1176 (2008)

    Article  ADS  CAS  Google Scholar 

  11. Milman, P. et al. A proposal to test Bell's inequalities with mesoscopic non-local states in cavity QED. Eur. Phys. J. D 32, 233–239 (2005)

    Article  ADS  CAS  Google Scholar 

  12. Wineland, D. J. et al. Experimental issues in coherent quantum-state manipulation of trapped atomic ions. J. Res. Natl. Inst. Stand. Technol. 103, 259–328 (1998)

    Article  CAS  Google Scholar 

  13. Cirac, J. I. & Zoller, P. A scalable quantum computer with ions in an array of microtraps. Nature 404, 579–581 (2000)

    Article  ADS  CAS  Google Scholar 

  14. Kielpinski, D., Monroe, C. & Wineland, D. Architecture for a large-scale ion-trap quantum computer. Nature 417, 709–711 (2002)

    Article  ADS  CAS  Google Scholar 

  15. Schleich, W. P. Quantum Optics in Phase Space 1st edn (Wiley-VCH, 2001)

    Book  Google Scholar 

  16. Aspect, A. in Quantum [Un]speakables — From Bell to Quantum Information (eds Bertlmann, R. A. & Zeilinger, A.) Ch. 9 (Springer, 2002)

    Google Scholar 

  17. Matsukevich, D. N., Maunz, P., Moehring, D. L., Olmschenk, S. & Monroe, C. Bell inequality violation with two remote atomic qubits. Phys. Rev. Lett. 100, 150404 (2008)

    Article  ADS  CAS  Google Scholar 

  18. Pan, J.-W., Chen, Z.-B., Zukowski, M., Weinfurter, H. & Zeilinger, A. Multi-photon entanglement and interferometry. Preprint at 〈http://arxiv.org/abs/0805.2853〉 (2008)

  19. Leibfried, D. et al. Experimental demonstration of a robust, high-fidelity geometrical two ion-qubit phase gate. Nature 422, 412–415 (2003)

    Article  ADS  CAS  Google Scholar 

  20. Rowe, M. A. et al. Transport of quantum states and separation of ions in a dual RF ion trap. Quant. Inform. Comput 2, 257–271 (2002)

    CAS  MATH  Google Scholar 

  21. Barrett, M. D. et al. Deterministic quantum teleportation of atomic qubits. Nature 429, 737–739 (2004)

    Article  ADS  CAS  Google Scholar 

  22. King, B. E. et al. Cooling the collective motion of trapped ions to initialize a quantum register. Phys. Rev. Lett. 81, 1525–1528 (1998)

    Article  ADS  CAS  Google Scholar 

  23. Kielpinski, D. et al. A decoherence-free quantum memory using trapped ions. Science 291, 1013–1015 (2001)

    Article  ADS  CAS  Google Scholar 

  24. Barrett, M. D. et al. Sympathetic cooling of 9Be+ and 24Mg+ for quantum logic. Phys. Rev. A 68, 042302 (2003)

    Article  ADS  Google Scholar 

  25. Vandersypen, L. M. K. & Chuang, I. L. NMR techniques for quantum control and computation. Rev. Mod. Phys. 76, 1037–1069 (2004)

    Article  ADS  Google Scholar 

  26. Sackett, C. A. et al. Experimental entanglement of four particles. Nature 404, 256–259 (2000)

    Article  ADS  CAS  Google Scholar 

  27. Ozeri, R. et al. Errors in trapped-ion quantum gates due to spontaneous photon scattering. Phys. Rev. A 75, 042329 (2007)

    Article  ADS  Google Scholar 

  28. Roos, C. F. et al. Nonlinear coupling of continuous variables at the single quantum level. Phys. Rev. A 77, 040302(R) (2008)

    Article  ADS  Google Scholar 

  29. Herrmann, M. et al. Frequency metrology on single trapped ions in the weak binding limit: The 3s 1/2 – 3p 3/2 transition in 24Mg+ . Phys. Rev. Lett. 102, 013006 (2009)

    Article  ADS  CAS  Google Scholar 

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Acknowledgements

This work was supported by IARPA and the NIST Quantum Information Program. We thank J. Britton, Y. Colombe and H. Uys for comments on the manuscript. J.P.H. acknowledges support from the Lindemann Trust fellowship. This paper is a contribution by the National Institute of Standards and Technology and not subject to US copyright.

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Authors and Affiliations

  1. Time and Frequency Division, National Institute of Standards and Technology, Boulder, Colorado 80305, USA,

    J. D. Jost, J. P. Home, J. M. Amini, D. Hanneke, J. J. Bollinger, D. Leibfried & D. J. Wineland

  2. Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100, Israel

    R. Ozeri

  3. Lockheed Martin, Denver, Colorado 80127, USA ,

    C. Langer

Authors
  1. J. D. Jost
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  2. J. P. Home
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  3. J. M. Amini
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  9. D. J. Wineland
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Correspondence to J. D. Jost.

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Jost, J., Home, J., Amini, J. et al. Entangled mechanical oscillators. Nature 459, 683–685 (2009). https://doi.org/10.1038/nature08006

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