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:

Generation of ultraviolet entangled photons in a semiconductor

Abstract

Entanglement is one of the key features of quantum information and communications technology. The method that has been used most frequently to generate highly entangled pairs of photons1,2 is parametric down-conversion. Short-wavelength entangled photons are desirable for generating further entanglement between three or four photons, but it is difficult to use parametric down-conversion to generate suitably energetic entangled photon pairs. One method that is expected to be applicable for the generation of such photons3 is resonant hyper-parametric scattering (RHPS): a pair of entangled photons is generated in a semiconductor via an electronically resonant third-order nonlinear optical process. Semiconductor-based sources of entangled photons would also be advantageous for practical quantum technologies, but attempts to generate entangled photons in semiconductors have not yet been successful4,5. Here we report experimental evidence for the generation of ultraviolet entangled photon pairs by means of biexciton resonant RHPS in a single crystal of the semiconductor CuCl. We anticipate that our results will open the way to the generation of entangled photons by current injection, analogous to current-driven single photon sources6,7.

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: Schematic diagram of the resonant hyper-parametric scattering (RHPS) via biexciton.
Figure 2: Experimental set-up to measure the photon correlation of the RHPS. A sample (CuCl thin crystal) was mounted in the cryostat, and its temperature was kept at 4 K.
Figure 3: Emission spectrum of the CuCl crystal at 4 K.
Figure 4: Photon correlation histogram between the photons emitted via the RHPS without polarization analysers.
Figure 5: Photon correlation histogram for linear polarization combinations HH, HV, VH, VV, DD, D , D, and , are shown where the first and second letters represent the polarizations of the two photons involved.
Figure 6: Graphical representation of the two-photon polarization density matrix reconstructed from the photon correlation measurements for 19 polarization combinations.

Similar content being viewed by others

References

  1. Kwiat, P. G. et al. New high-intensity source of polarization-entangled photon pairs. Phys. Rev. Lett. 75, 4337–4341 (1995)

    Article  ADS  CAS  Google Scholar 

  2. Kwiat, P. G. et al. Ultrabright source of polarization-entangled photons. Phys. Rev. A. 60, R773–R776 (1999)

    Article  ADS  CAS  Google Scholar 

  3. Strekalov, D. V. & Dowling, J. P. Two-photon interferometry for high-resolution imaging. J. Mod. Opt. 49, 519–527 (2002)

    Article  ADS  Google Scholar 

  4. Santori, C. et al. Polarization-correlated photon pairs from a single quantum dot. Phys. Rev. B 66, 045308 (2002)

    Article  ADS  Google Scholar 

  5. Stace, T. M., Milburn, G. J. & Barnes, C. H. W. Entangled two-photon source using biexciton emission of an asymmetric quantum dot in a cavity. Phys. Rev. B 67, 085317 (2003)

    Article  ADS  Google Scholar 

  6. Benson, O., Santori, C., Pelton, M. & Yamamoto, Y. Regulated and entangled photons from a single quantum dot. Phys. Rev. Lett. 84, 2513–2516 (1999)

    Article  ADS  Google Scholar 

  7. Yuan, Z. L. et al. Electrically driven single-photon source. Science 295, 102–105 (2002)

    Article  ADS  CAS  Google Scholar 

  8. Ueta, M. et al. in Excitonic Processes in Solids Ch. 3 (Springer, Berlin, 1986)

  9. Itoh, T. & Suzuki, T. Excitonic polariton-polariton resonance scattering via excitonic molecules in CuCl. J. Phys. Soc. Jpn 45, 1939–1948 (1978)

    Article  ADS  CAS  Google Scholar 

  10. Hönerlage, B. et al. The dispersion of excitons, polaritons and biexcitons in direct-gap semiconductors. Phys. Rep. 124, 161–253 (1985)

    Article  ADS  Google Scholar 

  11. Kuwata, M., Mita, T. & Nagasawa, N. Polarization rotation effects associated with the two-photon transition of Γ1 excitonic molecules in CuCl. Opt. Commun. 40, 208–211 (1982)

    Article  ADS  CAS  Google Scholar 

  12. Savasta, S., Martino, G. & Girlanda, R. Entangled photon pairs from the optical decay of biexcitons. Solid State Commun. 111, 495–500 (1999)

    Article  ADS  CAS  Google Scholar 

  13. Shimano, R., Svirko, Y. P., Mysyrowicz, A. & Kuwata-Gonokami, M. Efficient two-photon light amplification by a coherent biexciton wave. Phys. Rev. Lett. 89, 233601 (2002)

    Article  ADS  CAS  Google Scholar 

  14. Saba, M. et al. High-temperature ultrafast polariton parametric amplification in semiconductor microcavities. Nature 414, 731–735 (2001)

    Article  ADS  CAS  Google Scholar 

  15. James, D. F. V., Kwiat, P. G., Munro, W. J. & White, A. G. Measurement of qubits. Phys. Rev. A 64, 052312 (2001)

    Article  ADS  Google Scholar 

  16. White, A. G., James, D. F. V., Munro, W. J. & Kwiat, P. G. Exploring Hilbert space: Accurate characterization of quantum information. Phys. Rev. A 65, 01230 (2001)

    Article  MathSciNet  Google Scholar 

  17. Munro, W. J., Nemoto, K. & White, A. G. The Bell inequality: a measure of entanglement? J. Mod. Opt. 48, 1239–1246 (2001)

    ADS  MathSciNet  MATH  Google Scholar 

  18. Boto, A. N. et al. Quantum interferometric optical lithography: exploiting entanglement to beat the diffraction limit. Phys. Rev. Lett. 85, 2733–2736 (2000)

    Article  ADS  CAS  Google Scholar 

  19. Walter, P. et al. De Broglie wavelength of a non-local four-photon state. Nature 429, 158–161 (2004)

    Article  ADS  Google Scholar 

  20. Mitchell, M. W., Lundeen, J. S. & Steinberg, A. M. Super-resolving phase measurements with a multiphoton entangled state. Nature 429, 161–164 (2004)

    Article  ADS  CAS  Google Scholar 

Download references

Acknowledgements

We thank M. Hasegawa for his help in preparing samples. K.E. is grateful to P. G. Kwiat, M. Kuwata-Gonokami and H. Ishihara for discussions. This work was supported in part by the programme “Strategic Information and Communications R & D Promotion Scheme” of the Ministry of Public Management, Home Affairs, Posts and Telecommunications of Japan.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Keiichi Edamatsu.

Ethics declarations

Competing interests

The authors declare that they have no competing financial interests.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Edamatsu, K., Oohata, G., Shimizu, R. et al. Generation of ultraviolet entangled photons in a semiconductor. Nature 431, 167–170 (2004). https://doi.org/10.1038/nature02838

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature02838

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