Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Observation of one-way Einstein–Podolsky–Rosen steering

Subjects

Abstract

The distinctive non-classical features of quantum physics were first discussed in the seminal paper1 by A. Einstein, B. Podolsky and N. Rosen (EPR) in 1935. In his immediate response2, E. Schrödinger introduced the notion of entanglement, now seen as the essential resource in quantum information3,4,5 as well as in quantum metrology6,7,8. Furthermore, he showed that at the core of the EPR argument is a phenomenon that he called steering. In contrast to entanglement and violations of Bell's inequalities, steering implies a direction between the parties involved. Recent theoretical works have precisely defined this property, but the question arose as to whether there are bipartite states showing steering only in one direction9,10. Here, we present an experimental realization of two entangled Gaussian modes of light that in fact shows the steering effect in one direction but not in the other. The generated one-way steering gives a new insight into quantum physics and may open a new field of applications in quantum information.

This is a preview of subscription content, access via your institution

Access options

Rent or buy this article

Prices vary by article type

from$1.95

to$39.95

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Implications of inseparability criteria.
Figure 2: Gaussian one-way EPR steering visualized in phase space.
Figure 3: Schematic of the experimental set-up.
Figure 4: Certification of one-way steering.

References

  1. Einstein, A., Podolsky, B. & Rosen, N. Can quantum-mechanical description of physical reality be considered complete? Phys. Rev. 47, 777–780 (1935).

    Article  ADS  Google Scholar 

  2. Schrödinger, E. Discussion of probability relations between separated systems. Proc. Camb. Phil. Soc. 31, 555–563 (1935).

    Article  ADS  Google Scholar 

  3. Ekert, A. K. Quantum cryptography based on Bell's theorem. Phys. Rev. Lett. 67, 661–663 (1991).

    Article  ADS  MathSciNet  Google Scholar 

  4. Jennewein, T., Simon, C., Weihs, G., Weinfurter, H. & Zeilinger, A. Quantum cryptography with entangled photons. Phys. Rev. Lett. 84, 4729–4732 (2000).

    Article  ADS  Google Scholar 

  5. Braunstein, S. L. & van Loock, P. Quantum information with continuous variables. Rev. Mod. Phys. 77, 513–577 (2005).

    Article  ADS  MathSciNet  Google Scholar 

  6. Afek, I., Ambar, O. & Silberberg, Y. High-NOON states by mixing quantum and classical light. Science 328, 879–881 (2010).

    Article  ADS  MathSciNet  Google Scholar 

  7. Schnabel, R., Mavalvala, N., McClelland, D. E. & Lam, P. K. Quantum metrology for gravitational wave astronomy. Nature Commun. 121 (2010).

  8. The LIGO Scientific Collaboration. A gravitational wave observatory operating beyond the quantum shot-noise limit. Nature Phys. 7, 962–965 (2011).

  9. Wiseman, H. M., Jones, S. J. & Doherty, A. C. Steering, entanglement, nonlocality, and the Einstein–Podolsky–Rosen paradox. Phys. Rev. Lett. 98, 140402 (2007).

    Article  ADS  MathSciNet  Google Scholar 

  10. Cavalcanti, E. G., Jones, S. J., Wiseman, H. M. & Reid, M. D. Experimental criteria for steering and the Einstein–Podolsky–Rosen paradox. Phys. Rev. A 80, 032112 (2009).

    Article  ADS  Google Scholar 

  11. Ou, Z. Y., Pereira, S. F., Kimble, H. J. & Peng, K. C. Realization of the Einstein–Podolsky–Rosen paradox for continuous variables. Phys. Rev. Lett. 68, 3663–3666 (1992).

    Article  ADS  Google Scholar 

  12. Reid, M. D. et al. Colloquium: the Einstein–Podolsky–Rosen paradox: from concepts to applications. Rev. Mod. Phys. 81, 1727–1751 (2009).

    Article  ADS  MathSciNet  Google Scholar 

  13. Saunders, D. J., Jones, S. J., Wiseman, H. M. & Pryde, G. J. Experimental EPR-steering using Bell-local states. Nature Phys. 6, 845–849 (2010).

    Article  ADS  Google Scholar 

  14. Wittmann, B. et al. Loophole-free Einstein–Podolsky–Rosen experiment via quantum steering. New J. Phys. 14, 053030 (2012).

    Article  ADS  Google Scholar 

  15. Smith, D. H. et al. Conclusive quantum steering with superconducting transition-edge sensors. Nature Commun. 3, 625 (2012).

    Article  Google Scholar 

  16. Werner, R. F. Quantum states with Einstein–Podolsky–Rosen correlations admitting a hidden-variable model. Phys. Rev. A 40, 4277–4281 (1989).

    Article  ADS  Google Scholar 

  17. Wagner, K. et al. Entangling the spatial properties of laser beams. Science 321, 541–543 (2008).

    Article  ADS  Google Scholar 

  18. Midgley, S. L. W., Ferris, A. J. & Olsen, M. K. Asymmetric Gaussian steering: when Alice and Bob disagree. Phys. Rev. A 81, 022101 (2010).

    Article  ADS  Google Scholar 

  19. Reid, M. D. Demonstration of the Einstein–Podolsky–Rosen paradox using nondegenerate parametric amplification. Phys. Rev. A 40, 913–923 (1989).

    Article  ADS  Google Scholar 

  20. Eberle, T. et al. Gaussian entanglement for quantum key distribution from a single-mode squeezing source. Preprint at http://arXiv.org/abs.1110.3977 (2011).

  21. DiGuglielmo, J. et al. Experimental unconditional preparation and detection of a continuous bound entangled state of light. Phys. Rev. Lett. 107, 240503 (2011).

    Article  ADS  Google Scholar 

  22. Eberle, T. et al. Strong Einstein–Podolsky–Rosen entanglement from a single squeezed light source. Phys. Rev. A 83, 052329 (2011).

    Article  ADS  Google Scholar 

Download references

Acknowledgements

The authors thank J. Duhme for helpful discussions. This research was supported by EU FP 7 project QESSENCE (grant agreement no. 248095). V.H., T.E., S.S. and A.S. acknowledge support from the IMPRS on Gravitational Wave Astronomy. T.F. and R.F.W. acknowledge support from EU FP 7 project COQUIT (grant agreement no. 233747) and BMBF project QuoRep.

Author information

Authors and Affiliations

Authors

Contributions

V.H., T.E. and R.S. conceived the experiment. V.H. and T.E. conducted the experiment and performed all measurements with the help of S.S. and A.S. and under the supervision of R.S. Theoretical analysis was carried out by T.F. with supervision from R.F.W.

Corresponding author

Correspondence to Roman Schnabel.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Händchen, V., Eberle, T., Steinlechner, S. et al. Observation of one-way Einstein–Podolsky–Rosen steering. Nature Photon 6, 596–599 (2012). https://doi.org/10.1038/nphoton.2012.202

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nphoton.2012.202

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing