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.

  • Letter
  • Published:

Quantum mechanical complementarity probed in a closed-loop Aharonov–Bohm interferometer

Abstract

The complementarity principle1 demands that a particle reveals wave-like properties only when the different paths that it can take are indistinguishable2,3. The complementarity has been demonstrated in optics with pairs of correlated photons4,5 and in two-path solid-state interferometers with phase-coherent electrons6. In the latter experiment, a charge detector embedded near one path of a two-path electron interferometer provided which-path information3. Here, we report on electron dephasing in an Aharonov–Bohm ring interferometer7 via a charge detector adjacent to the ring. In contrast to the two-path interferometer, charge detection in the ring does not always provide path information. The interference was suppressed only when path information could be acquired, even if only in principle. This confirms that dephasing is not always induced by ‘disturbing’ the interfering particle through the interferometer–environment interactions: path information of the particle must be available too. Our experiment suggests that acquisition of which-path information is more fundamental than the back-action in understanding quantum mechanical complementarity.

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

Access options

Buy this article

USD 39.95

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

Figure 1: Which-path interferometer.
Figure 2: Detection procedure and Aharonov–Bohm oscillation.
Figure 3: Time-resolving measurements on the second-harmonic interference.

Similar content being viewed by others

References

  1. Bohr, N. in Quantum Theory and Measurement (eds Wheeler, J. A. & Zurek, W. H.) 9–49 (Princeton Univ. Press, Princeton, 1983).

    Google Scholar 

  2. Feynman, R., Leighton, R. & Sands, M. The Feynman Lectures on Physics Vol. III, Ch. 1 (Addison Wesley, Reading, 1965).

    MATH  Google Scholar 

  3. Stern, A., Aharonov, Y. & Imry, Y. Phase uncertainty and loss of interference: A general picture. Phys. Rev. A 41, 3436–3448 (1990).

    Article  ADS  Google Scholar 

  4. Zou, X. Y., Wang, L. J. & Mandel, L. Induced coherence and indistinguishability in optical interference. Phys. Rev. Lett. 67, 318–321 (1991).

    Article  ADS  Google Scholar 

  5. Dürr, S., Nonn, T. & Rempe, G. Origin of quantum-mechanical complementarity probed by a ‘which-way’ experiment in an atom interferometer. Nature 395, 33–37 (1998).

    Article  ADS  Google Scholar 

  6. Buks, E., Schuster, R., Heiblum, M., Mahalu, D. & Umansky, V. Dephasing in electron interference by a ‘which-path’ detector. Nature 391, 871–874 (1998).

    Article  ADS  Google Scholar 

  7. Yacoby, A., Heiblum, M., Mahalu, D. & Shtrikman, H. Coherence and phase sensitive measurements in a quantum dot. Phys. Rev. Lett. 74, 4047–4050 (1995).

    Article  ADS  Google Scholar 

  8. Schuster, R. et al. Phase measurement in a quantum dot via a double-slit interference experiment. Nature 385, 417–420 (1997).

    Article  ADS  Google Scholar 

  9. Field, M. et al. Measurements of Coulomb blockade with a noninvasive voltage probe. Phys. Rev. Lett. 70, 1311–1314 (1993).

    Article  ADS  Google Scholar 

  10. Sprinzak, D., Ji, Y., Heiblum, M., Mahalu, D. & Shtrikman, H. Charge distribution in a Kondo-correlated quantum dot. Phys. Rev. Lett. 88, 176805 (2002).

    Article  ADS  Google Scholar 

  11. Avinun-Kalish, M., Heiblum, M., Zarchin, O., Mahalu, D. & Umansky, V. Crossover from ‘mesoscopic’ to ‘universal’ phase for electron transmission in quantum dots. Nature 436, 529–533 (2005).

    Article  ADS  Google Scholar 

  12. Khym, G. L. & Kang, K. Charge detection in a closed-loop Aharonov–Bohm interferometer. Phys. Rev. B 74, 153309 (2006).

    Article  ADS  Google Scholar 

  13. Aharonov, Y. & Bohm, D Significance of electromagnetic potentials in the quantum theory. Phy. Rev. 115, 485–491 (1959).

    Article  ADS  MathSciNet  Google Scholar 

  14. Aronov, A. G. & Sharvin, Yu. V. Magnetic flux effects in disordered conductors. Rev. Mod. Phys. 59, 755–779 (1987).

    Article  ADS  Google Scholar 

  15. Avinun-Kalish, M., Heiblum, M., Silva, A., Mahalu, D. & Umansky, V. Controlled dephasing of a quantum dot in the Kondo regime. Phys. Rev. Lett. 92, 156801 (2004).

    Article  ADS  Google Scholar 

  16. Aleiner, I. L., Wingreen, N. S. & Meir, Y. Dephasing and the orthogonality catastrophe in tunneling through a quantum dot: “The which path?” interferometer. Phys. Rev. Lett. 79, 3740–3743 (1997).

    Article  ADS  Google Scholar 

  17. Gurvitz, S. A. Measurements with a noninvasive detector and dephasing mechanism. Phys. Rev. B 56, 15215–15223 (1997).

    Article  ADS  Google Scholar 

  18. Levinson, Y. Dephasing in a quantum dot due to coupling with a quantum point contact. Europhys. Lett. 39, 299–304 (1997).

    Article  ADS  Google Scholar 

  19. Stodolsky, L. Measurement process in a variable-barrier system. Phys. Lett. B 459, 193–200 (1999).

    Article  ADS  Google Scholar 

  20. Sprinzak, D., Buks, E., Heiblum, M. & Shtrikman, H. Controlled dephasing of electrons via a phase sensitive detector. Phys. Rev. Lett. 84, 5820–5823 (2000).

    Article  ADS  Google Scholar 

  21. Kang, K. Decoherence of the Kondo singlet via a quantum point contact detector. Phys. Rev. Lett. 95, 206808 (2005).

    Article  ADS  Google Scholar 

  22. Buttiker, M. & Martin, A. M. Charge relaxation and dephasing in Coulomb-coupled conductors. Phys. Rev. B 61, 2737–2741 (2000).

    Article  ADS  Google Scholar 

  23. Levinson, Y. Quantum dot dephasing by edge states. Phys. Rev. B 61, 4748–4753 (2000).

    Article  ADS  Google Scholar 

  24. Hackenbroich, G. Phase coherent transmission through interacting mesoscopic systems. Phys. Rep. 343, 463–538 (2001).

    Article  ADS  Google Scholar 

Download references

Acknowledgements

H.-J.L. was supported by the Electron Spin Science Center in POSTECH and the Pure Basic Research Program (Grant No. R01-2006-000-11248-0) administered by the Korea Science and Engineering Foundation (KOSEF), by the Korea Research Foundation (Grant No. KRF-2005-070-C00055) and by the POSTECH Core Research Program. Y.C. was supported by the Korea Foundation for International Cooperation of Science and Technology (KICOS; Grant No. 2006-04969), Nanoscopia Center of Excellence (NCoE; Grant No. M60504000249-06A0400-24910) at Hanyang University through a grant provided by the Korean Ministry of Science & Technology, and the Priority Research Centers Program (Grant No. KRF-2006-005-J02801) funded by KRF. K.K. was also supported by KRF (Grant No. KRF-2006-331-C00016). M.H. wishes to acknowledge the partial support of the MINERVA foundation, the German Israeli foundation (GIF), the German Israeli project cooperation (DIP), the Israeli Science foundation (ISF) and the Korea Ministry of Science and Technology program.

Author information

Authors and Affiliations

Authors

Corresponding authors

Correspondence to Yunchul Chung or Hu-Jong Lee.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Chang, DI., Khym, G., Kang, K. et al. Quantum mechanical complementarity probed in a closed-loop Aharonov–Bohm interferometer. Nature Phys 4, 205–209 (2008). https://doi.org/10.1038/nphys854

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue date:

  • DOI: https://doi.org/10.1038/nphys854

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