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:

Observation of the fractional quantum Hall effect in an oxide

Nature Materials volume 9, pages 889–893 (2010)Cite this article

Subjects

Abstract

The quantum Hall effect arises from the cyclotron motion of charge carriers in two-dimensional systems. However, the ground states related to the integer and fractional quantum Hall effect, respectively, are of entirely different origin1,2,3,4,5. The former can be explained within a single-particle picture; the latter arises from electron correlation effects governed by Coulomb interaction. The prerequisite for the observation of these effects is extremely smooth interfaces of the thin film layers to which the charge carriers are confined. So far, experimental observations of such quantum transport phenomena have been limited to a few material systems based on silicon, III–V compounds and graphene1,2,3,4,5,6,7,8,9. In ionic materials, the correlation between electrons is expected to be more pronounced than in the conventional heterostructures, owing to a large effective mass of charge carriers. Here we report the observation of the fractional quantum Hall effect in MgZnO/ZnO heterostructures grown by molecular-beam epitaxy, in which the electron mobility exceeds 180,000 cm2 V−1 s−1. Fractional states such as ν=4/3, 5/3 and 8/3 clearly emerge, and the appearance of the ν=2/5 state is indicated. The present study represents a technological advance in oxide electronics that provides opportunities to explore strongly correlated phenomena in quantum transport of dilute carriers.

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: Transport properties of MgZnO/ZnO field-effect heterostructures.
Figure 2: Comparison of electron–electron interaction and scattering time in some material systems.
Figure 3: FQHE at 0.06 K.
Figure 4: Determination of the activation energy for ν=4/3, 5/3 and 8/3 states.

Similar content being viewed by others

References

  1. v. Klitzing, K., Dorda, G. & Pepper, M. New method for high-accuracy determination of the fine-structure constant based on quantized Hall resistance. Phys. Rev. Lett. 45, 494–497 (1980).

    Article  Google Scholar 

  2. Tsui, D. C., Stormer, H. L. & Gossard, A. C. Two-dimensional magnetotransport in the extreme quantum limit. Phys. Rev. Lett. 48, 1559–1562 (1982).

    Article  CAS  Google Scholar 

  3. Willett, R. et al. Observation of an even-denominator quantum number in the fractional quantum Hall effect. Phys. Rev. Lett. 59, 1776–1779 (1987).

    Article  CAS  Google Scholar 

  4. Das Sarma, S. & Pinczuk, A. Perspectives in Quantum Hall Effects (Wiley-VCH, 1997).

    Google Scholar 

  5. Manfra, M. J., Pfeiffer, L. N., West, K. W., de Picciotto, R. & Baldwin, K. W. High mobility two-dimensional hole system in GaAs/AlGaAs quantum wells grown on (100) GaAs substrates. Appl. Phys. Lett. 86, 162106 (2005).

    Article  Google Scholar 

  6. Nelson, S. F. et al. Observation of the fractional quantum Hall effect in Si/SiGe heterostructures. Appl. Phys. Lett. 61, 64–66 (1992).

    Article  CAS  Google Scholar 

  7. De Poortere, E. P. et al. Enhanced electron mobility and high order fractional quantum Hall states in AlAs quantum wells. Appl. Phys. Lett. 80, 1583–1585 (2002).

    Article  CAS  Google Scholar 

  8. Du, X., Skachko, I., Duerr, F., Luican, A. & Andrei, E. Y. Fractional quantum Hall effect and insulating phase of Dirac electrons in graphene. Nature 462, 192–195 (2009).

    Article  CAS  Google Scholar 

  9. Bolotin, K. I., Ghahari, F., Shulman, M. D., Stormer, H. L. & Kim, P. Observation of the fractional quantum Hall effect in graphene. Nature 462, 196–199 (2009).

    Article  CAS  Google Scholar 

  10. Ohtomo, A. & Hwang, H. Y. A high-mobility electron gas at the LaAlO3/SrTiO3 heterointerface. Nature 427, 423–426 (2004).

    Article  CAS  Google Scholar 

  11. Tsukazaki, A. et al. Quantum Hall effect in polar oxide heterostructures. Science 315, 1388–1391 (2007).

    Article  CAS  Google Scholar 

  12. Caviglia, A. D. et al. Electric field control of the LaAlO3/SrTiO3 interface ground state. Nature 456, 624–627 (2008).

    Article  CAS  Google Scholar 

  13. Son, J. et al. Epitaxial SrTiO3 films with electron mobilities exceeding 30,000 cm2 V−1 s−1. Nature Mater. 9, 482–484 (2010).

    Article  CAS  Google Scholar 

  14. Tsukazaki, A. et al. Spin susceptibility and effective mass of two-dimensional electrons in MgxZn1−xO/ZnO heterostructures. Phys. Rev. B 78, 233308 (2008).

    Article  Google Scholar 

  15. Pfeiffer, L., West, K. W., Stormer, H. L. & Baldwin, K. W. Electron mobilities exceeding 107 cm2/Vs in modulation-doped GaAs. Appl. Phys. Lett. 55, 1888–1890 (1989).

    Article  CAS  Google Scholar 

  16. Sajoto, T., Suen, Y. W., Engel, L. W., Santos, M. B. & Shayegan, M. Fractional quantum Hall effect in very-low-density GaAs/AlxGa1−xAs heterostructures. Phys. Rev. B 41, 8449–8460 (1990).

    Article  CAS  Google Scholar 

  17. Umansky, V. et al. MBE growth of ultra-low disorder 2DEG with mobility exceeding 35×106 cm2/Vs. J. Cryst. Growth 311, 1658–1661 (2009).

    Article  CAS  Google Scholar 

  18. Manfra, M. J. et al. Electron mobility exceeding 160000 cm2/Vs in AlGaN/GaN heterostructures grown by molecular-beam epitaxy. Appl. Phys. Lett. 85, 5394–5396 (2004).

    Article  CAS  Google Scholar 

  19. Manfra, M. J. et al. Transport and percolation in a low-density high-mobility two-dimensional hole system. Phys. Rev. Lett. 99, 236402 (2007).

    Article  CAS  Google Scholar 

  20. Du, R. R., Stormer, H. L., Tsui, D. C., Pfeiffer, L. N. & West, K. W. Experimental evidence for new particles in the fractional quantum Hall effect. Phys. Rev. Lett. 70, 2944–2947 (1993).

    Article  CAS  Google Scholar 

  21. Boebinger, G. S. et al. Activation energies and localization in the fractional quantum Hall effect. Phys. Rev. B 36, 7919–7929 (1987).

    Article  CAS  Google Scholar 

  22. Willett, R. L., Stormer, H. L., Tsui, D. C., Gossard, A. C. & English, J. H. Quantitative experimental test for the theoretical gap energies in the fractional quantum Hall effect. Phys. Rev. B 37, 8476–8479 (1988).

    Article  CAS  Google Scholar 

  23. Lai, K., Pan, W., Tsui, D. C. & Xie, Y-H. Fractional quantum Hall effect at ν=2/3 and 4/3 in strained Si quantum wells. Phys. Rev. B 69, 125337 (2004).

    Article  Google Scholar 

  24. Dean, C. R. et al. Intrinsic gap of the ν=5/2 fractional quantum Hall state. Phys. Rev. Lett. 100, 146803 (2008).

    Article  CAS  Google Scholar 

  25. Pan, W. et al. Experimental studies of the fractional quantum Hall effect in the first excited Landau level. Phys. Rev. B 77, 075307 (2008).

    Article  Google Scholar 

  26. Choi, H. C., Kang, W., Das Sarma, S., Pfeiffer, L. N. & West, K. W. Activation gaps of fractional quantum Hall effect in the second Landau level. Phys. Rev. B 77, 081301 (2008).

    Article  Google Scholar 

  27. Ghosh, S. et al. Room-temperature spin coherence in ZnO. Appl. Phys. Lett. 86, 232507 (2005).

    Article  Google Scholar 

  28. Baer, W. S. Faraday rotation in ZnO: Determination of the electron effective mass. Phys. Rev. 154, 785–789 (1967).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We wish to thank H. Aoki and D. Chiba for fruitful discussions and T. Kita for experimental help. A.T. is supported by the Japan Society for the Promotion of Science (JSPS) through its ‘Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST Program).’ A.O. and M.K. are supported by the Asahi Glass Foundation.

Author information

Authors and Affiliations

  1. Quantum-Phase Electronics Center and Department of Applied Physics, The University of Tokyo, Tokyo 113-8656, Japan

    A. Tsukazaki

  2. PRESTO, Japan Science and Technology Agency (JST), Tokyo 102-0075, Japan

    A. Tsukazaki

  3. Interdisciplinary Devices R&D Center, ROHM Co. Ltd., Kyoto 615-8585, Japan

    S. Akasaka & K. Nakahara

  4. Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577, Japan

    Y. Ohno & H. Ohno

  5. WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan

    D. Maryenko & M. Kawasaki

  6. Department of Applied Chemistry, Tokyo Institute of Technology, Tokyo 152-8552, Japan

    A. Ohtomo

  7. Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan

    M. Kawasaki

  8. CREST, Japan Science and Technology Agency (JST), Tokyo 102-0075, Japan

    M. Kawasaki

Authors
  1. A. Tsukazaki
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. S. Akasaka
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. K. Nakahara
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Y. Ohno
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. H. Ohno
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. D. Maryenko
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. A. Ohtomo
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. M. Kawasaki
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

A.T., A.O. and M.K. designed this research; A.T. carried out the experiments; A.T. and D.M. analysed the data; S.A. and K.N. fabricated the sample; Y.O. and H.O. contributed to the experimental set-up; and all authors co-wrote the manuscript.

Corresponding authors

Correspondence to A. Tsukazaki or M. Kawasaki.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Information

Supplementary Information (PDF 557 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Tsukazaki, A., Akasaka, S., Nakahara, K. et al. Observation of the fractional quantum Hall effect in an oxide. Nature Mater 9, 889–893 (2010). https://doi.org/10.1038/nmat2874

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nmat2874

This article is cited by

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