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.

  • Article
  • Published:

Progressive field-state collapse and quantum non-demolition photon counting

Abstract

The irreversible evolution of a microscopic system under measurement is a central feature of quantum theory. From an initial state generally exhibiting quantum uncertainty in the measured observable, the system is projected into a state in which this observable becomes precisely known. Its value is random, with a probability determined by the initial system’s state. The evolution induced by measurement (known as ‘state collapse’) can be progressive, accumulating the effects of elementary state changes. Here we report the observation of such a step-by-step collapse by non-destructively measuring the photon number of a field stored in a cavity. Atoms behaving as microscopic clocks cross the cavity successively. By measuring the light-induced alterations of the clock rate, information is progressively extracted, until the initially uncertain photon number converges to an integer. The suppression of the photon number spread is demonstrated by correlations between repeated measurements. The procedure illustrates all the postulates of quantum measurement (state collapse, statistical results and repeatability) and should facilitate studies of non-classical fields trapped in cavities.

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

Access options

Buy this article

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

Figure 1: Principle of QND photon counting.
Figure 2: Progressive collapse of field into photon number state.
Figure 3: Reconstructed photon number distribution.
Figure 4: Repeated QND measurements.

Similar content being viewed by others

References

  1. Wheeler, J. A. & Zurek, W. H. Quantum Theory and Measurement (Princeton Series in Physics, Princeton, New Jersey, 1983)

    Book  Google Scholar 

  2. Kuzmich, A., Mandel, L. & Bigelow, N. P. Generation of spin squeezing via continuous quantum non-demolition measurement. Phys. Rev. Lett. 85, 1594–1597 (2000)

    Article  ADS  CAS  Google Scholar 

  3. Geremia, J. M., Stockton, J. K. & Mabuchi, H. Suppression of spin projection noise in broadband atomic magnetometry. Phys. Rev. Lett. 94, 203002 (2005)

    Article  ADS  CAS  Google Scholar 

  4. Braginsky, V. B. & Vorontsov, Y. I. Quantum mechanical limitations in macroscopic experiments and modern experimental technique. Usp. Fiz. Nauk 114, 41–53 (1974); Sov. Phys. Usp. 17, 644–650 (1975)

    Article  ADS  Google Scholar 

  5. Thorne, K. S., Drever, R. W. P., Caves, C. M., Zimmerman, M. & Sandberg, V. D. Quantum nondemolition measurements of harmonic oscillators. Phys. Rev. Lett. 40, 667–671 (1978)

    Article  ADS  Google Scholar 

  6. Unruh, W. G. Analysis of quantum nondemolition measurement. Phys. Rev. D 18, 1764–1772 (1978)

    Article  ADS  Google Scholar 

  7. Caves, C. M., Thorne, K. S., Drever, R. W. P., Sandberg, V. D. & Zimmerman, M. On the measurement of a weak classical force coupled to a quantum mechanical oscillator. Rev. Mod. Phys. 52, 341–392 (1980)

    Article  ADS  Google Scholar 

  8. Milburn, G. J. & Walls, D. F. Quantum nondemolition measurements via quadratic coupling. Phys. Rev. A 28, 2065–2070 (1983)

    Article  ADS  Google Scholar 

  9. Peil, S. & Gabrielse, G. Observing the quantum limit of an electron cyclotron: QND measurement of quantum jumps between Fock states. Phys. Rev. Lett. 83, 1287–1290 (1999)

    Article  ADS  CAS  Google Scholar 

  10. Leibfried, D., Blatt, R., Monroe, C. & Wineland, D. J. Quantum dynamics of single trapped ions. Rev. Mod. Phys. 75, 281–324 (2003)

    Article  ADS  CAS  Google Scholar 

  11. Schmidt, P. O. et al. Spectroscopy using quantum logic. Science 309, 749–752 (2005)

    Article  ADS  CAS  Google Scholar 

  12. Kuzmich, A. et al. Quantum non-demolition measurements of collective atomic spin. Phys. Rev. A 60, 2346–2350 (1999)

    Article  ADS  CAS  Google Scholar 

  13. Grangier, P., Levenson, J. A. & Poizat, J. P. Quantum non-demolition measurements in optics. Nature 396, 537–542 (1998)

    Article  ADS  CAS  Google Scholar 

  14. Imoto, N., Haus, H. A. & Yamamoto, Y. Quantum nondemolition measurement of the photon number via the optical Kerr effect. Phys. Rev. A 32, 2287–2292 (1985)

    Article  ADS  CAS  Google Scholar 

  15. Grangier, P., Roch, J. F. & Roger, G. Observation of backaction-evading measurement of an optical intensity in a three-level atomic non-linear system. Phys. Rev. Lett. 66, 1418–1421 (1991)

    Article  ADS  CAS  Google Scholar 

  16. Roch, J. F. et al. Quantum nondemolition measurements using cold trapped atoms. Phys. Rev. Lett. 78, 634–637 (1997)

    Article  ADS  CAS  Google Scholar 

  17. Bencheikh, K., Levenson, J. A., Grangier, P. & Lopez, O. Quantum nondemolition demonstration via repeated backaction evading measurements. Phys. Rev. Lett. 75, 3422–3425 (1995)

    Article  ADS  CAS  Google Scholar 

  18. Bruckmeier, R., Schneider, K., Schiller, S. & Mlynek, J. Quantum nondemolition measurements improved by a squeezed meter input. Phys. Rev. Lett. 78, 1243–1246 (1997)

    Article  ADS  CAS  Google Scholar 

  19. Haroche, S. in Fundamental Systems in Quantum Optics (eds Dalibard, J. & Raimond, J. M.) 767–940 (Les Houches Summer School, Session LIII, North Holland, Amsterdam, 1992)

    Google Scholar 

  20. Haroche, S. & Raimond, J. M. Exploring the Quantum: Atoms, Cavities and Photons (Oxford Univ. Press, Oxford, UK, 2006)

    Book  Google Scholar 

  21. Walther, H., Varcoe, B. T. H., Englert, B. G. & Becker, T. Cavity quantum electrodynamics. Rep. Prog. Phys. 69, 1325–1382 (2006)

    Article  ADS  Google Scholar 

  22. Birnbaum, K. M. et al. Photon blockade in an optical cavity with one trapped atom. Nature 436, 87–90 (2005)

    Article  ADS  CAS  Google Scholar 

  23. Wilk, T., Webster, S. C., Kuhn, A. & Rempe, G. Single-atom single-photon quantum interface. Science doi: 10.1126/science.1143835 (published online 21 June 2007)

  24. Nogues, G. et al. Seeing a single photon without destroying it. Nature 400, 239–242 (1999)

    Article  ADS  CAS  Google Scholar 

  25. Varcoe, B. T. H., Brattke, S., Weidinger, M. & Walther, H. Preparing pure photon number states of the radiation field. Nature 403, 743–746 (2000)

    Article  ADS  CAS  Google Scholar 

  26. Raimond, J. M., Brune, M. & Haroche, S. Manipulating quantum entanglement with atoms and photons in a cavity. Rev. Mod. Phys. 73, 565–582 (2001)

    Article  ADS  MathSciNet  Google Scholar 

  27. Schuster, D. I. et al. Resolving photon number states in a superconducting circuit. Nature 445, 515–518 (2007)

    Article  ADS  CAS  Google Scholar 

  28. Kuhr, S. et al. Ultrahigh finesse Fabry-Pérot superconducting resonator. Appl. Phys. Lett. 90, 164101 (2007)

    Article  ADS  Google Scholar 

  29. Gleyzes, S. et al. Quantum jumps of light recording the birth and death of a photon in a cavity. Nature 446, 297–300 (2007)

    Article  ADS  CAS  Google Scholar 

  30. Brune, M., Haroche, S., Lefèvre, V., Raimond, J. M. & Zagury, N. Quantum non-demolition measurement of small photon numbers by Rydberg atom phase-sensitive detection. Phys. Rev. Lett. 65, 976–979 (1990)

    Article  ADS  CAS  Google Scholar 

  31. Brune, M., Haroche, S., Raimond, J. M., Davidovich, L. & Zagury, N. Quantum non-demolition measurements and generation of Schrödinger cat states. Phys. Rev. A 45, 5193–5214 (1992)

    Article  CAS  Google Scholar 

  32. Carmichael, H. An Open System Approach to Quantum Optics (Springer, Berlin, 1993)

    Book  Google Scholar 

  33. Nielsen, M. A. & Chuang, I. L. Quantum Computation and Quantum Information (Cambridge Univ. Press, Cambridge, UK, 2000)

    MATH  Google Scholar 

  34. Glauber, R. J. Coherent and incoherent states of the radiation field. Phys. Rev. 131, 2766–2788 (1963)

    Article  ADS  MathSciNet  Google Scholar 

  35. D’Ariano, G. M. & Yuen, H. P. Impossibility of measuring the wave function of a single quantum system. Phys. Rev. Lett. 76, 2832–2835 (1996)

    Article  ADS  Google Scholar 

  36. Gisin, N., Ribordy, G. G., Tittel, W. & Zbinden, H. Quantum cryptography. Rev. Mod. Phys. 74, 145–195 (2002)

    Article  ADS  Google Scholar 

  37. Ramsey, N. Molecular Beams (Oxford Univ. Press, Oxford, UK, 1984)

    Google Scholar 

  38. Bayes, T. An essay towards solving a problem in the doctrine of chances. Phil. Trans. R. Soc. Lond. 53, 370–418 (1763)

    Article  MathSciNet  Google Scholar 

  39. Lu, N. Effects of dissipation on photon statistics and the lifetime of a pure number state. Phys. Rev. A 40, 1707–1708 (1989)

    Article  ADS  CAS  Google Scholar 

  40. Maître, X. et al. Quantum memory with a single photon in a cavity. Phys. Rev. Lett. 79, 769–772 (1997)

    Article  ADS  Google Scholar 

  41. Bertet, P. et al. Generating and probing a two-photon Fock state with a single atom in a cavity. Phys. Rev. Lett. 88, 143601 (2002)

    Article  ADS  CAS  Google Scholar 

  42. Brune, M. et al. Observing the progressive decoherence of the meter in a quantum measurement. Phys. Rev. Lett. 77, 4887–4890 (1996)

    Article  ADS  CAS  Google Scholar 

  43. Bertet, P. et al. Direct measurement of the Wigner function of a one photon Fock state in a cavity. Phys. Rev. Lett. 89, 200402 (2002)

    Article  ADS  CAS  Google Scholar 

  44. Giulini, D. et al. Decoherence and the Appearance of a Classical World in Quantum Theory (Springer, Berlin, 1996)

    Book  Google Scholar 

  45. Zurek, W. H. Decoherence, einselection and the quantum origins of the classical. Rev. Mod. Phys. 75, 715–775 (2003)

    Article  ADS  MathSciNet  Google Scholar 

  46. Osnaghi, S. et al. Coherent control of an atomic collision in a cavity. Phys. Rev. Lett. 87, 037902 (2001)

    Article  ADS  CAS  Google Scholar 

  47. Haroche, S., Brune, M. & Raimond, J. M. Measuring photon numbers in a cavity by atomic interferometry: optimizing the convergence procedure. J. Phys. II France 2, 659–670 (1992)

    Article  CAS  Google Scholar 

Download references

Acknowledgements

This work was supported by the Agence Nationale pour la Recherche (ANR), by the Japan Science and Technology Agency (JST), and by the EU under the IP projects SCALA and CONQUEST. C.G. and S.D. were funded by the Délégation Générale à l’Armement (DGA). J.-M.R. is a member of the Institut Universitaire de France (IUF).

Author information

Authors and Affiliations

Authors

Corresponding authors

Correspondence to Michel Brune or Serge Haroche.

Ethics declarations

Competing interests

Reprints and permissions information is available at www.nature.com/reprints. The authors declare no competing financial interests.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Guerlin, C., Bernu, J., Deléglise, S. et al. Progressive field-state collapse and quantum non-demolition photon counting. Nature 448, 889–893 (2007). https://doi.org/10.1038/nature06057

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature06057

This article is cited by

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.

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