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Ferromagnetic dislocations in antiferromagnetic NiO

Abstract

Crystal lattice defects often degrade device functionality1,2, but engineering these defects may have value in future electronic and magnetic device applications. For example, dislocations—one-dimensional lattice defects with locally distinct atomic-scale structures3,4—exhibit unique and localized electrical properties5,6 and can be used as a template for producing conducting nanowires in insulating crystals7,8,9,10,11. It has also been predicted that spin-polarized current may flow along dislocations in topological insulators12. Although it is expected that the magnetic properties of dislocations will differ from those of the lattice5,13,14, their fundamental characterization at the individual level has received little attention. Here, we demonstrate that dislocations in NiO crystals show unique magnetic properties. Magnetic force microscopy imaging clearly reveals ferromagnetic ordering of individual dislocations in antiferromagnetic NiO, originating from the local non-stoichiometry of the dislocation cores. The ferromagnetic dislocations have high coercivity due to their strong interaction with the surrounding antiferromagnetic bulk phase. Although it has already been reported that nanocrystals of rock-salt NiO show ferromagnetic behaviour15, our study characterizes the ferromagnetic properties of individual lattice defects. We discuss the origin of the unexpected ferromagnetism in terms of the physical properties of the atomic-scale core structures of single dislocations, and demonstrate that it is possible to fabricate stable nanoscale magnetic elements inside crystalline environments composed of these microstructures.

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Figure 1: Ferromagnetic dislocations in the NiO thin film.
Figure 2: Magnetic hysteresis loop of dislocations in the NiO thin film.
Figure 3: Atomic-scale structures of the dislocation cores in the NiO thin film.
Figure 4: Electronic structures of the dislocations in NiO.

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References

  1. Hÿtch, M. J., Putaux, J. L. & Penisson, J. M. Measurement of the displacement field of dislocations to 0.03 Å by electron microscopy. Nature 423, 270–273 (2003).

    Article  Google Scholar 

  2. Son, J. et al. Epitaxial SrTiO3 films with electron mobilities exceeding 30,000 cm2/V·s. Nature Mater. 6, 482–484 (2010).

    Article  Google Scholar 

  3. Ikuhara, Y. & Pirouz, P. High resolution transmission electron microscopy studies of metal/ceramics interfaces. Microsc. Res. Tech. 40, 206–241 (1998).

    Article  CAS  Google Scholar 

  4. Stoneham, A. M. Theory of Defects in Solids (Clarendon, 1985).

  5. Szot, K., Speier, W., Bihlmayer, G. & Waser, R. Switching the electrical resistance of individual dislocations in single-crystalline SrTiO3 . Nature Mater. 5, 313–320 (2006).

    Article  Google Scholar 

  6. Chu, M. et al. Impact of misfit dislocations on the polarization instability of epitaxial nanostructured ferroelectric perovskites. Nature Mater. 3, 87–90 (2004).

    Article  CAS  Google Scholar 

  7. Nakamura, A., Matsunaga, K., Tohma, J., Yamamoto, T. & Ikuhara, Y. Conducting nanowires in insulating ceramics. Nature Mater. 2, 453–456 (2003).

    Article  CAS  Google Scholar 

  8. Ikuhara, Y. Nanowire design by dislocation technology. Prog. Mater. Sci. 54, 770–791 (2009).

    Article  CAS  Google Scholar 

  9. Tokumoto, Y. et al. Fabrication of electrically conductive nanowires using high-density dislocations in AlN thin films. J. Appl. Phys. 106, 124307 (2009).

    Article  Google Scholar 

  10. Amma, S. et al. Electrical current flow at conductive nanowires formed in GaN thin films by a dislocation template technique. Appl. Phys. Lett. 96, 193109 (2010).

    Article  Google Scholar 

  11. Kioseoglou, J. et al. Screw threading dislocations in AlN: structural and electronic properties of In and O doped material. J. Appl. Phys. 110, 053715 (2011).

    Article  Google Scholar 

  12. Ran, Y., Zhang, Y. & Vishwanath, A. One-dimensional topologically protected modes in topological insulators with lattice dislocations. Nature Phys. 5, 298–303 (2009).

    Article  CAS  Google Scholar 

  13. Seeger, A., Rieger, H., Trauble, H. & Kronmuller, H. Effect of lattice defects on magnetization curve of ferromagnets. J. Appl. Phys. 35, 740–748 (1964).

    Article  Google Scholar 

  14. Nakagawa, K., Maeda, K. & Takuechi, S. Plastic deformation of CdTe single crystals II. Photoplastic effect of II–VI compounds. J. Phys. Soc. Jpn 50, 3040–3046 (1981).

    Article  CAS  Google Scholar 

  15. Bi, H., Li, S., Zhang, Y. & Du, Y. Ferromagnetic-like behavior of ultrafine NiO nanocrystallites. J. Magn. Magn. Mater. 277, 363–367 (2004).

    Article  CAS  Google Scholar 

  16. Haberle, T. et al. Towards quantitative magnetic force microscopy: theory and experiment. New J. Phys. 14, 043044 (2012).

    Article  Google Scholar 

  17. Sebastian, A., Salapaka, M. V., Chen, D. J. & Cleveland, J. P. Harmonic and power balance tools for tapping-mode atomic force microscope. J. Appl. Phys. 89, 6473–6480 (2001).

    Article  CAS  Google Scholar 

  18. Maruyama, S., Gervais, A. & Philibert, A. Transmission electron microscopy on nickel oxide single crystals deformed at room temperature. J. Mater. Sci. 17, 2384–2390 (1982).

    Article  CAS  Google Scholar 

  19. Ohta, J., Suzuki, K. & Suzuki, T. High-resolution electron microscopy of dislocations of MgO. J. Mater. Res. 9, 2953–2958 (1994).

    Article  CAS  Google Scholar 

  20. Foitzik, A., Haasen, P. & Skrotzki, W. High resolution TEM of dissociated dislocations in PbS. Phil. Mag. A 64, 29–37 (1991).

    Article  CAS  Google Scholar 

  21. Wang, Z. C., Tsukimoto, S., Saito, M. & Ikuhara, Y. Individual charge-trapping dislocations in an ionic insulator. Appl. Phys. Lett. 95, 184101 (2009).

    Article  Google Scholar 

  22. Reinert, F. et al. Electron and hole doping in NiO. Z. Phys. B 97, 83–93 (1995).

    Article  CAS  Google Scholar 

  23. Koyama, Y., Mizoguchi, T., Ikeno, H. & Tanaka, I. Electronic structure of lithium nickel oxide by electron energy loss spectroscopy. J. Phys. Chem. B 109, 10749–10755 (2005).

    Article  CAS  Google Scholar 

  24. Shimomura, Y., Kojima, M. & Saito, S. Crystal structure of ferromagnetic nickel oxide. J. Phys. Soc. Jpn 11, 1136–1146 (1956).

    Article  CAS  Google Scholar 

  25. Nogues, J. et al. Exchange bias in nanostructures. Phys. Rep. 422, 65–117 (2005).

    Article  Google Scholar 

  26. Wei, M. et al. Room temperature ferromagnetism in bulk Mn-Doped Cu2O. Appl. Phys. Lett. 86, 072514 (2005).

    Article  Google Scholar 

  27. Lin, Y-H., Zhan, B., Nan, C-W., Zhao, R. & Xu, X. Ferromagnetism in antiferromagnetic NiO-based thin film. J. Appl. Phys. 110, 043921 (2011).

    Article  Google Scholar 

  28. Zippel, J. et al. Defect-induced ferromagnetism in undoped and Mn-doped zirconia thin films. Phys. Rev. B 82, 125209 (2010).

    Article  Google Scholar 

  29. Wollschläger, J. et al. Stoichiometry and morphology of MgO films grown reactively on Ag(100). Appl. Surf. Sci. 142, 129–134 (1999).

    Article  Google Scholar 

  30. Joshi, U. S., Takahashi, R., Matsumoto, Y. & Koinuma, H. Structure of NiO and Li-doped NiO single crystalline thin layers with atomically flat surface. Thin Solid Films 486, 214–217 (2005).

    Article  CAS  Google Scholar 

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Acknowledgements

This study was supported in part by the Grant-in-Aid for Scientific Research from the Japan Society for the Promotion of Science (JSPS) and the Ministry of Education, Culture, Sports and Technology (MEXT). I.S. and S.K. were supported as JSPS research fellows. N.S. acknowledges support from JST-PRESTO and JSPS KAKENHI Grant number 23686093. This work was conducted in the research Hub for Advanced Nano Characterization, the University of Tokyo, supported by MEXT. Part of this work was performed using the facilities of the Cryogenic Research Center at the University of Tokyo. Calculations were conducted on supercomputers at the ISSP, the University of Tokyo.

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I.S. carried out the experiments and wrote the paper. N.S. designed the experiments and wrote the paper. Z.W. carried out the DFT calculations. T.Y. designed and conducted the experiments. S.K. supported and advised the experiments. Y.I. discussed the results and directed the entire study. All authors read and commented on the manuscript.

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Correspondence to Yuichi Ikuhara.

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The authors declare no competing financial interests.

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Sugiyama, I., Shibata, N., Wang, Z. et al. Ferromagnetic dislocations in antiferromagnetic NiO. Nature Nanotech 8, 266–270 (2013). https://doi.org/10.1038/nnano.2013.45

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