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Robust isothermal electric control of exchange bias at room temperature

Abstract

Voltage-controlled spin electronics is crucial for continued progress in information technology. It aims at reduced power consumption, increased integration density and enhanced functionality where non-volatile memory is combined with high-speed logical processing. Promising spintronic device concepts use the electric control of interface and surface magnetization. From the combination of magnetometry, spin-polarized photoemission spectroscopy, symmetry arguments and first-principles calculations, we show that the (0001) surface of magnetoelectric Cr2O3 has a roughness-insensitive, electrically switchable magnetization. Using a ferromagnetic Pd/Co multilayer deposited on the (0001) surface of a Cr2O3 single crystal, we achieve reversible, room-temperature isothermal switching of the exchange-bias field between positive and negative values by reversing the electric field while maintaining a permanent magnetic field. This effect reflects the switching of the bulk antiferromagnetic domain state and the interface magnetization coupled to it. The switchable exchange bias sets in exactly at the bulk Néel temperature.

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Figure 1: Structural characterization.
Figure 2: Spin-polarized UPS measurements and layer-resolved DOS.
Figure 3: Isothermal electric switching of the exchange-bias field.
Figure 4: Hysteretic electric-field dependence of the exchange-bias field.

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References

  1. Wolf, S. A. et al. Spintronics: A spin-based electronics vision for the future. Science 294, 1488–1495 (2001).

    Article  CAS  Google Scholar 

  2. Žutić, I., Fabian, J. & Das Sarma, S. Spintronics: Fundamentals and applications. Rev. Mod. Phys. 76, 323–410 (2004).

    Article  Google Scholar 

  3. Zhirnov, V. V., Hutchby, J. A., Bourianoff, G. I. & Brewer, J. E. Emerging research logic devices. IEEE Circuits Devices 21, 37–46 (2005).

    Article  Google Scholar 

  4. Ney, A., Pampuch, C., Koch, R. & Ploog, K. H. Programmable computing with a single magnetoresistive element. Nature 425, 485–487 (2003).

    Article  CAS  Google Scholar 

  5. Binek, Ch. & Doudin, B. Magnetoelectronics with magnetoelectrics. J. Phys. Condens. Matter 17, L39–L44 (2005).

    Article  CAS  Google Scholar 

  6. Dery, H., Dalal, P., Cywiński, Ł. & Sham, L. J. Spin-based logic in semiconductors for reconfigurable large-scale circuits. Nature 447, 573–576 (2007).

    Article  CAS  Google Scholar 

  7. Zavaliche, F. et al. Electrically assisted magnetic recording in multiferroic nanostructures. Nano Lett. 7, 1586–1590 (2007).

    Article  CAS  Google Scholar 

  8. Tsymbal, E. Y. & Kohlstedt, H. Applied physics: Tunneling across a ferroelectric. Science 313, 181–183 (2006).

    Article  CAS  Google Scholar 

  9. Maruyama, T. et al. Large voltage-induced magnetic anisotropy change in a few atomic layers of iron. Nature Nanotech. 4, 158–161 (2008).

    Article  Google Scholar 

  10. Velev, J. P., Dowben, P. A., Tsymbal, E. Y., Jenkins, S. J. & Caruso, A. N. Interface effects in spin-polarized metal/insulator layered structures. Surf. Sci. Rep. 63, 400–425 (2008).

    Article  CAS  Google Scholar 

  11. Nogués, J. & Schuller, I. K. Exchange bias. J. Magn. Magn. Mater. 192, 203–232 (1999).

    Article  Google Scholar 

  12. Chappert, C., Fert, A. & Van Dau, F. N. The emergence of spin electronics in data storage. Nature Mater. 6, 813–823 (2007).

    Article  CAS  Google Scholar 

  13. Borisov, P., Hochstrat, A., Chen, X., Kleemann, W. & Binek, Ch. Magnetoelectric switching of exchange bias. Phys. Rev. Lett. 94, 117203 (2005).

    Article  Google Scholar 

  14. O’Dell, T. H. The Electrodynamics of Magneto–Electric Media (North-Holland, 1970).

    Google Scholar 

  15. Borisov, P., Hochstrat, A., Shvartsman, V. V. & Kleemann, W. Superconducting quantum interference device setup for magnetoelectric measurements. Rev. Sci. Instrum. 78, 106105 (2007).

    Article  CAS  Google Scholar 

  16. Fiebig, M. Revival of the magnetoelectric effect. J. Phys. D 38, R123–R152 (2005).

    Article  CAS  Google Scholar 

  17. Wang, J. et al. Epitaxial BiFeO3 multiferroic thin film heterostructures. Science 299, 1719–1722 (2003).

    Article  CAS  Google Scholar 

  18. Hur, N. et al. Electric polarization reversal and memory in a multiferroic material induced by magnetic fields. Nature 429, 392–395 (2004).

    Article  CAS  Google Scholar 

  19. Eerenstein, W., Mathur, N. D. & Scott, J. F. Multiferroic and magnetoelectric materials. Nature 442, 759–765 (2006).

    Article  CAS  Google Scholar 

  20. Bibes, M. & Barthélémy, A. Multiferroics: Towards a magnetoelectric memory. Nature Mater. 7, 425–426 (2008).

    Article  CAS  Google Scholar 

  21. Lottermoser, T. et al. Magnetic phase control by an electric field. Nature 430, 541–544 (2004).

    Article  CAS  Google Scholar 

  22. Sahoo, S. et al. Ferroelectric control of magnetism in BaTiO3/Fe heterostructures via interface strain coupling. Phys. Rev. B 76, 092108 (2007).

    Article  Google Scholar 

  23. Weiler, M. et al. Voltage controlled inversion of magnetic anisotropy in a ferromagnetic thin film at room temperature. New J. Phys. 11, 013021 (2009).

    Article  Google Scholar 

  24. Laukhin, V. et al. Electric-field control of exchange bias in multiferroic epitaxial heterostructures. Phys. Rev. Lett. 97, 227201 (2006).

    Article  CAS  Google Scholar 

  25. Chu, Y-H. et al. Electric-field control of local ferromagnetism using a magnetoelectric multiferroic. Nature Mater. 7, 478–482 (2008).

    Article  CAS  Google Scholar 

  26. Zhao, T. et al. Electrical control of antiferromagnetic domains in multiferroic BiFeO3 films at room temperature. Nature Mater. 5, 823–829 (2006).

    Article  CAS  Google Scholar 

  27. Liu, J. P., Fullerton, E., Gutfleisch, O. & Sellmyer, D. J. (eds) in Nanoscale Magnetic Materials and Applications Ch. 6 (Springer, 2009).

  28. Lim, S-H. et al. Exchange bias in thin-film (Co/Pt)3/Cr2O3 multilayers. J. Magn. Magn. Mater. 321, 1955–1958 (2009).

    Article  CAS  Google Scholar 

  29. Kuch, W. et al. Tuning the magnetic coupling across ultrathin antiferromagnetic films by controlling atomic-scale roughness. Nature Mater. 5, 128–133 (2006).

    Article  CAS  Google Scholar 

  30. Krichevtsov, B. B., Pavlov, V. V. & Pisarev, R. V. Nonreciprocal optical effects in antiferromagnetic Cr2O3 subjected to electric and magnetic fields. Zh. Eksp. Teor. Fiz. 94, 284–295 (1988).

    CAS  Google Scholar 

  31. Freund, H-J., Kuhlenbeck, H. & Staemmler, V. Oxide surfaces. Rep. Prog. Phys. 59, 283–347 (1996).

    Article  CAS  Google Scholar 

  32. Martin, T. J. & Anderson, J. C. Antiferromagnetic domain switching in Cr2O3 . IEEE Trans. Magn. 2, 446–449 (1966).

    Article  Google Scholar 

  33. Bromwich, T. J. et al. Remanent magnetic states and interactions in nano-pillars. Nanotechnology 17, 4367–4373 (2006).

    Article  CAS  Google Scholar 

  34. Kresse, G. & Hafner, J. Ab initio molecular dynamics for open-shell transition metals. Phys. Rev. B 48, 13115–13118 (1993).

    Article  CAS  Google Scholar 

  35. Kresse, G. & Furthmueller, J. Efficiency of ab inito energy calculations for metals and semiconductors using a plane-wave basis set. Comput. Mater. Sci. 6, 15–50 (1996).

    Article  CAS  Google Scholar 

  36. Kresse, G. & Furthmueller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54, 11169–11186 (1996).

    Article  CAS  Google Scholar 

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Acknowledgements

This work is supported by NSF through Career DMR-0547887, by the Nebraska Research Initiative (NRI), by the NSF MRSEC Grant No. 0820521 and by the NRC/NRI supplement to MRSEC. K.D.B. is a Cottrell Scholar of Research Corporation. Technical help from S-Q. Shi, V. R. Shah and L. P. Yue in the calculation of DOS, taking XRD and AFM data is acknowledged, respectively. We are thankful to Crystal GmbH for providing excellent Cr2O3 single crystals.

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Contributions

X.H. and C.B. designed the study, in particular conceiving the electrically controlled exchange bias and electrically controlled magnetism. Y.W. and X.H. collected and analysed the magnetic data. N.W. led the photoemission experiments and data analysis. A.C. and E.V. supported the photoemission experiments. K.D.B. conceived the concept of roughness-insensitive surface magnetization and directed the electronic structure calculations. P.A.D. directed and conceived the photoemission experiments. C.B. directed the overall study. All authors contributed to the scientific process and the refinement of the manuscript. C.B. and X.H. wrote most of the paper.

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Correspondence to Christian Binek.

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The authors declare no competing financial interests.

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He, X., Wang, Y., Wu, N. et al. Robust isothermal electric control of exchange bias at room temperature. Nature Mater 9, 579–585 (2010). https://doi.org/10.1038/nmat2785

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