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:

Generating single microwave photons in a circuit

Nature volume 449, pages 328–331 (2007)Cite this article

Abstract

Microwaves have widespread use in classical communication technologies, from long-distance broadcasts to short-distance signals within a computer chip. Like all forms of light, microwaves, even those guided by the wires of an integrated circuit, consist of discrete photons1. To enable quantum communication between distant parts of a quantum computer, the signals must also be quantum, consisting of single photons, for example. However, conventional sources can generate only classical light, not single photons. One way to realize a single-photon source2 is to collect the fluorescence of a single atom. Early experiments measured the quantum nature of continuous radiation3,4, and further advances allowed triggered sources of photons on demand5,6,7,8,9,10,11. To allow efficient photon collection, emitters are typically placed inside optical or microwave cavities12,13,14,15,16,17,18,19, but these sources are difficult to employ for quantum communication on wires within an integrated circuit. Here we demonstrate an on-chip, on-demand single-photon source, where the microwave photons are injected into a wire with high efficiency and spectral purity. This is accomplished in a circuit quantum electrodynamics architecture20, with a microwave transmission line cavity that enhances the spontaneous emission of a single superconducting qubit. When the qubit spontaneously emits, the generated photon acts as a flying qubit, transmitting the quantum information across a chip. We perform tomography of both the qubit and the emitted photons, clearly showing that both the quantum phase and amplitude are transferred during the emission. Both the average power and voltage of the photon source are characterized to verify performance of the system. This single-photon source is an important addition to a rapidly growing toolbox for quantum optics on a chip.

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

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

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

Figure 1: The circuit quantum electrodynamics device for generating single photons.
Figure 2: Enhanced spontaneous emission through the Purcell effect.
Figure 3: Output of a single-photon source.
Figure 4: Direct observation of the free induction decay of a superconducting qubit.
Figure 5: Mapping the qubit state onto the photon state.

Similar content being viewed by others

References

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

    Article  CAS  ADS  Google Scholar 

  2. Oxborrow, M. & Sinclair, A. Single-photon sources. Contemp. Phys. 46, 173–206 (2005)

    Article  ADS  Google Scholar 

  3. Clauser, J. F. Experimental distinction between the quantum and classical field-theoretic predictions for the photoelectric effect. Phys. Rev. D 9, 853–860 (1974)

    Article  CAS  ADS  Google Scholar 

  4. Kimble, H. J., Dagenais, M. & Mandel, L. Photon antibunching in resonance fluorescence. Phys. Rev. Lett. 39, 691–695 (1977)

    Article  CAS  ADS  Google Scholar 

  5. Diedrich, F. & Walther, H. Nonclassical radiation of a single stored ion. Phys. Rev. Lett. 58, 203–206 (1987)

    Article  CAS  ADS  Google Scholar 

  6. Basche, T., Moerner, W. E., Orrit, M. & Talon, H. Photon antibunching in the fluorescence of a single dye molecule trapped in a solid. Phys. Rev. Lett. 69, 1516–1519 (1992)

    Article  CAS  ADS  Google Scholar 

  7. Brunel, C., Lounis, B., Tamarat, P. & Orrit, M. Triggered source of single photons based on controlled single molecule fluorescence. Phys. Rev. Lett. 83, 2722–2725 (1999)

    Article  CAS  ADS  Google Scholar 

  8. Lounis, B. & Moerner, W. E. Single photons on demand from a single molecule at room temperature. Nature 407, 491–493 (2000)

    Article  CAS  ADS  Google Scholar 

  9. Kurtsiefer, C., Mayer, S., Zarda, P. & Weinfurter, H. Stable solid-state source of single photons. Phys. Rev. Lett. 85, 290–293 (2000)

    Article  CAS  ADS  Google Scholar 

  10. Michler, P. et al. Quantum correlation among photons from a single quantum dot at room temperature. Nature 406, 968–970 (2000)

    Article  CAS  ADS  Google Scholar 

  11. Darquie, B. et al. Controlled single-photon emission from a single trapped two-level atom. Science 309, 454–456 (2005)

    Article  CAS  ADS  Google Scholar 

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

    Article  CAS  ADS  Google Scholar 

  13. Brattke, S., Varcoe, B. T. H. & Walther, H. Generation of photon number states on demand via cavity quantum electrodynamics. Phys. Rev. Lett. 86, 3534–3537 (2001)

    Article  CAS  ADS  Google Scholar 

  14. Moreau, E. et al. Single-mode solid-state single photon source based on isolated quantum dots in pillar microcavities. Appl. Phys. Lett. 79, 2865–2867 (2001)

    Article  CAS  ADS  Google Scholar 

  15. Santori, C., Fattal, D., Vuckovic, J., Solomon, G. S. & Yamamoto, Y. Indistinguishable photons from a single-photon device. Nature 419, 594–597 (2002)

    Article  CAS  ADS  Google Scholar 

  16. Pelton, M. et al. Efficient source of single photons: A single quantum dot in a micropost microcavity. Phys. Rev. Lett. 89, 233602 (2002)

    Article  ADS  Google Scholar 

  17. Kuhn, A., Hennrich, M. & Rempe, G. Deterministic single-photon source for distributed quantum networking. Phys. Rev. Lett. 89, 067901 (2002)

    Article  ADS  Google Scholar 

  18. McKeever, J. et al. Deterministic generation of single photons from one atom trapped in a cavity. Science 303, 1992–1994 (2004)

    Article  CAS  ADS  Google Scholar 

  19. Keller, M., Lange, B., Hayasaka, K., Lange, W. & Walther, H. Continuous generation of single photons with controlled waveform in an ion-trap cavity system. Nature 431, 1075–1078 (2004)

    Article  CAS  ADS  Google Scholar 

  20. Blais, A., Huang, R.-S., Wallraff, A., Girvin, S. M. & Schoelkopf, R. J. Cavity quantum electrodynamics for superconducting electrical circuits: An architecture for quantum computation. Phys. Rev. A. 69, 062320 (2004)

    Article  ADS  Google Scholar 

  21. Purcell, E. M. Spontaneous emission probabilities at radio frequencies. Phys. Rev. 69, 681 (1946)

    Article  Google Scholar 

  22. Koch, J. et al. Charge insensitive qubit design derived from the Cooper pair box. Phys. Rev. A (in the press); preprint at 〈http://arxiv.org/cond-mat/0703002〉 (2007)

  23. Bouchiat, V., Vion, D., Joyez, P., Esteve, D. & Devoret, M. H. Quantum coherence with a single cooper pair. Phys. Scr. T76, 165–170 (1998)

    Article  CAS  ADS  Google Scholar 

  24. Wallraff, A. et al. Strong coupling of a single photon to a superconducting qubit using circuit quantum electrodynamics. Nature 431, 162–167 (2004)

    Article  CAS  ADS  Google Scholar 

  25. Wallraff, A. et al. Approaching unit visibility for control of a superconducting qubit with dispersive readout. Phys. Rev. Lett. 95, 060501–060504 (2005)

    Article  CAS  ADS  Google Scholar 

  26. Steffen, M. et al. State tomography of capacitively shunted phase qubits with high fidelity. Phys. Rev. Lett. 97, 050502 (2006)

    Article  ADS  Google Scholar 

  27. Smithey, D. T., Beck, M., Raymer, M. G. & Faridani, A. Measurement of the Wigner distribution and the density matrix of a light mode using optical homodyne tomography: application to squeezed states and the vacuum. Phys. Rev. Lett. 70, 1244–1247 (1993)

    Article  CAS  ADS  Google Scholar 

  28. Leonhardt, U. Measuring the Quantum State of Light (Cambridge Univ. Press, 1997)

    MATH  Google Scholar 

  29. DiVincenzo, D. P. The physical implementation of quantum computation Fortschr. Phys. 48, 771–783 (2000)

    MATH  Google Scholar 

Download references

Acknowledgements

This work was supported in part by the National Security Agency under the Army Research Office, the NSF, and Yale University. A.A.H. acknowledges support from Yale University via a Quantum Information and Mesoscopic Physics Fellowship.

Author information

Author notes

  1. A. A. Houck and D. I. Schuster: These authors contributed equally to this work.

Authors and Affiliations

  1. Departments of Applied Physics and Physics, Yale University, New Haven, Connecticut 06520, USA,

    A. A. Houck, D. I. Schuster, J. M. Gambetta, J. A. Schreier, B. R. Johnson, J. M. Chow, L. Frunzio, J. Majer, M. H. Devoret, S. M. Girvin & R. J. Schoelkopf

Authors
  1. A. A. Houck
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. D. I. Schuster
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. J. M. Gambetta
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. J. A. Schreier
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. B. R. Johnson
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. J. M. Chow
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. L. Frunzio
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. J. Majer
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. M. H. Devoret
    View author publications

    You can also search for this author in PubMed Google Scholar

  10. S. M. Girvin
    View author publications

    You can also search for this author in PubMed Google Scholar

  11. R. J. Schoelkopf
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to R. J. Schoelkopf.

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

Houck, A., Schuster, D., Gambetta, J. et al. Generating single microwave photons in a circuit. Nature 449, 328–331 (2007). https://doi.org/10.1038/nature06126

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature06126

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

Advanced 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