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.

Exciton condensation and perfect Coulomb drag

Nature volume 488, pages 481–484 (2012)Cite this article

Subjects

Abstract

Coulomb drag is a process whereby the repulsive interactions between electrons in spatially separated conductors enable a current flowing in one of the conductors to induce a voltage drop in the other1,2,3. If the second conductor is part of a closed circuit, a net current will flow in that circuit. The drag current is typically much smaller than the drive current owing to the heavy screening of the Coulomb interaction. There are, however, rare situations in which strong electronic correlations exist between the two conductors. For example, double quantum well systems can support exciton condensates, which consist of electrons in one well tightly bound to holes in the other4,5,6. ‘Perfect’ drag is therefore expected; a steady transport current of electrons driven through one quantum well should be accompanied by an equal current of holes in the other7. Here we demonstrate this effect, taking care to ensure that the electron–hole pairs dominate the transport and that tunnelling of charge between the quantum wells, which can readily compromise drag measurements, is negligible. We note that, from an electrical engineering perspective, perfect Coulomb drag is analogous to an electrical transformer that functions at zero frequency.

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

Relevant articles

Open Access articles citing this article.

Access options

Buy article

Get time limited or full article access on ReadCube.

$32.00

Buy

All prices are NET prices.

Figure 1: Corbino conductance at ν T = 1.
Figure 2: Corbino Coulomb drag.
Figure 3: Four-terminal versus two-terminal tunnelling characteristics at ν T = 1.
Figure 4: Coulomb drag current ratio, I2/I1 at νT = 1.

References

  1. Pogrebinsky, M. B. Mutual drag of carriers in a semiconductor-insulator-semiconductor system. Fiz. Tekh. Poluprovodn. 11, 637–644 (1977); Sov.. Phys. Semicond. 11, 372–376 (1977)

    Google Scholar 

  2. Price, P. M. Hot electron effects in heterolayers. Physica B 117, 750–752 (1983)

    Article  Google Scholar 

  3. Rojo, A. G. Electron-drag effects in coupled electron systems. J. Phys. Condens. Matter 11, R31–R52 (1999)

    Article  ADS  MathSciNet  CAS  Google Scholar 

  4. Snoke, D. Spontaneous Bose coherence of excitons and polaritons. Science 298, 1368–1372 (2002)

    Article  ADS  CAS  Google Scholar 

  5. Butov, L. V. Exciton condensation in coupled quantum wells. Solid State Commun. 127, 89–98 (2003)

    Article  ADS  CAS  Google Scholar 

  6. Eisenstein, J. P. & MacDonald, A. H. Bose-Einstein condensation of excitons in bilayer electron systems. Nature 432, 691–694 (2004)

    Article  ADS  CAS  Google Scholar 

  7. Su, J.-J. & MacDonald, A. H. How to make a bilayer exciton condensate flow. Nature Phys. 4, 799–802 (2008)

    Article  ADS  CAS  Google Scholar 

  8. Fertig, H. A. Energy spectrum of a layered system in a strong magnetic field. Phys. Rev. B 40, 1087–1095 (1989)

    Article  ADS  CAS  Google Scholar 

  9. MacDonald, A. H. & Girvin, S. M. in Perspectives in Quantum Hall Effects (eds Das Sarma, S. & Pinczuk, A. ) 161–224 (Wiley, 1997)

    Google Scholar 

  10. Spielman, I. B., Eisenstein, J. P., Pfeiffer, L. N. & West, K. W. Resonantly enhanced tunneling in a double layer quantum Hall ferromagnet. Phys. Rev. Lett. 84, 5808–5811 (2000)

    Article  ADS  CAS  Google Scholar 

  11. Kellogg, M., Eisenstein, J. P., Pfeiffer, L. N. & West, K. W. Vanishing Hall resistance at high magnetic field in a double-layer two-dimensional electron system. Phys. Rev. Lett. 93, 036801 (2004)

    Article  ADS  CAS  Google Scholar 

  12. Tutuc, E., Shayegan, M. & Huse, D. A. Counterflow measurements in strongly correlated GaAs hole bilayers: evidence for electron-hole pairing. Phys. Rev. Lett. 93, 036802 (2004)

    Article  ADS  CAS  Google Scholar 

  13. Wiersma, R. et al. Activated transport in the separate layers that form the ν T = 1 exciton condensate. Phys. Rev. Lett. 93, 266805 (2004)

    Article  ADS  CAS  Google Scholar 

  14. Yang, S. Hammack, A. T., Fogler, M. M., Butov, L. V. & Gossard, A. C. Coherence length of cold exciton gases in coupled quantum wells. Phys. Rev. Lett. 97, 187402 (2006)

    Article  ADS  Google Scholar 

  15. High, A. A. et al. Spontaneous coherence in a cold exciton gas. Nature 483, 584–588 (2012)

    Article  ADS  CAS  Google Scholar 

  16. Kasprzak, J. et al. Bose-Einstein condensation of exciton polaritons. Nature 443, 409–414 (2006)

    Article  ADS  CAS  Google Scholar 

  17. Tiemann, L. et al. Exciton condensate at a total filling factor of one in Corbino two-dimensional electron bilayers. Phys. Rev. B 77, 033306 (2008)

    Article  ADS  Google Scholar 

  18. Tiemann, L., Dietsche, W., Hauser, M. & von Klitzing, K. Critical tunneling currents in the regime of bilayer excitons. N. J. Phys. 10, 045018 (2008)

    Article  Google Scholar 

  19. Finck, A. D. K., Eisenstein, J. P., Pfeiffer, L. N. & West, K. W. Exciton transport and Andreev reflection in a bilayer quantum Hall system. Phys. Rev. Lett. 106, 236807 (2011)

    Article  ADS  CAS  Google Scholar 

  20. Eisenstein, J. P., Pfeiffer, L. N. & West, K. W. Independently contacted two-dimensional electron systems in double quantum wells. Appl. Phys. Lett. 57, 2324–2326 (1990)

    Article  ADS  CAS  Google Scholar 

  21. Spielman, I. B., Eisenstein, J. P., Pfeiffer, L. N. & West, K. W. Observation of a linearly dispersing Goldstone mode in a quantum Hall ferromagnet. Phys. Rev. Lett. 87, 036803 (2001)

    Article  ADS  CAS  Google Scholar 

  22. Tiemann, L. & Yoon, Y. Dietsche, W. von Klitzing, K. & Wegscheider, W. Dominant parameters for the critical tunneling current in bilayer exciton condensates. Phys. Rev. B 80, 165120 (2009)

    Article  ADS  Google Scholar 

  23. Huse, D. A. Resistance due to vortex motion in the ν = 1 bilayer quantum Hall superfluid. Phys. Rev. B 72, 064514 (2005)

    Article  ADS  Google Scholar 

  24. Fertig, H. A. &. Murthy, G. Coherence network in the quantum Hall bilayer. Phys. Rev. Lett. 95, 156802 (2005)

    Article  ADS  CAS  Google Scholar 

  25. Fil, D. V. & Shevchenko, S. I. Interlayer tunneling and the problem of superfluidity in bilayer quantum Hall systems. Low Temp. Phys. 33, 780–782 (2007)

    Article  ADS  CAS  Google Scholar 

  26. Lee, D. K. K., Eastham, P. R. & Cooper, N. R. Breakdown of counterflow superfluidity in a disordered quantum Hall bilayer. Adv. Condens. Matter Phys. 2011, 792125 (2011)

    Article  Google Scholar 

  27. Pesin, D. A. & MacDonald, A. H. Scattering theory of transport in coherent quantum Hall bilayers. Phys. Rev. B 84, 075308 (2011)

    Article  ADS  Google Scholar 

Download references

Acknowledgements

We thank A.H. MacDonald and D. Pesin for discussions. This work was supported by NSF grant DMR-1003080.

Author information

Authors and Affiliations

  1. Condensed Matter Physics, California Institute of Technology, Pasadena, 91125, California, USA

    D. Nandi, A. D. K. Finck & J. P. Eisenstein

  2. Department of Electrical Engineering, Princeton University, Princeton, 08544, New Jersey, USA

    L. N. Pfeiffer & K. W. West

Authors
  1. D. Nandi
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. A. D. K. Finck
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. J. P. Eisenstein
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. L. N. Pfeiffer
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. K. W. West
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

D.N., A.D.K.F. and J.P.E. conceived the project. L.N.P. and K.W.W. grew the samples. D.N. and A.D.K.F. performed the experiment and, along with J.P.E., analysed the data and wrote the manuscript.

Corresponding author

Correspondence to J. P. Eisenstein.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

PowerPoint slides

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Nandi, D., Finck, A., Eisenstein, J. et al. Exciton condensation and perfect Coulomb drag. Nature 488, 481–484 (2012). https://doi.org/10.1038/nature11302

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature11302

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