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Room-temperature antiskyrmions and sawtooth surface textures in a non-centrosymmetric magnet with S4 symmetry

Nature Materials volume 20, pages 335–340 (2021)Cite this article

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Abstract

Topological spin textures have attracted much attention both for fundamental physics and spintronics applications. Among them, antiskyrmions possess a unique spin configuration with Bloch-type and Néel-type domain walls owing to anisotropic Dzyaloshinskii–Moriya interaction in the non-centrosymmetric crystal structure. However, antiskyrmions have thus far only been observed in a few Heusler compounds with D2d symmetry. Here we report a new material, Fe1.9Ni0.9Pd0.2P, in a different symmetry class (S4), in which antiskyrmions exist over a wide temperature range that includes room temperature, and transform into skyrmions on changing magnetic field and lamella thickness. The periodicity of magnetic textures greatly depends on the crystal thickness, and domains with anisotropic sawtooth fractals were observed at the surface of thick crystals and attributed to the interplay between the dipolar interaction and the Dzyaloshinskii–Moriya interaction as governed by crystal symmetry. Our findings provide an arena in which to study antiskyrmions, and should stimulate further research on topological spin textures and their applications.

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Fig. 1: Antiskyrmions and basic properties of Fe1.9Ni0.9Pd0.2P.
Fig. 2: Magnetic textures in a lamella with a thickness t ≈ 130 nm.
Fig. 3: Lamella-thickness-dependent transformation between skyrmions and antiskyrmions.
Fig. 4: Thickness evolution of topological spin textures.

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All the data presented in the article and Supplementary Information are available from the corresponding authors upon reasonable request.

References

  1. Nagaosa, N. & Tokura, Y. Topological properties and dynamics of magnetic skyrmions. Nat. Nanotechnol. 8, 899–911 (2013).

    Article  CAS  Google Scholar 

  2. Bogdanov, A. N. & Yablonskii, D. A. Thermodynamically stable ‘vortices’ in magnetically ordered crystals. The mixed state of magnets. Sov. Phys. JETP 68, 101–103 (1989).

    Google Scholar 

  3. Leonov, A. O. et al. The properties of isolated chiral skyrmions in thin magnetic films. New J. Phys. 18, 065003 (2016).

    Article  Google Scholar 

  4. Mühlbauer, S. et al. Skyrmion lattice in a chiral magnet. Science 323, 915–919 (2009).

    Article  Google Scholar 

  5. Yu, X. Z. et al. Real-space observation of a two-dimensional skyrmion crystal. Nature 465, 901–904 (2010).

    Article  CAS  Google Scholar 

  6. Seki, S., Yu, X. Z., Ishiwata, S. & Tokura, Y. Observation of skyrmions in a multiferroic material. Science 336, 198–201 (2012).

    Article  CAS  Google Scholar 

  7. Tokunaga, Y. et al. A new class of chiral materials hosting magnetic skyrmions beyond room temperature. Nat. Commun. 6, 7638–7644 (2015).

    Article  CAS  Google Scholar 

  8. Heinze, S. et al. Spontaneous atomic-scale magnetic skyrmion lattice in two dimensions. Nat. Phys. 7, 713–718 (2011).

    Article  CAS  Google Scholar 

  9. Woo, S. et al. Observation of room-temperature magnetic skyrmions and their current-driven dynamics in ultrathin metallic ferromagnets. Nat. Mater. 15, 501–506 (2016).

    Article  CAS  Google Scholar 

  10. Pollard, S. D. et al. Observation of stable Néel skyrmions in cobalt/palladium multilayers with Lorentz transmission electron microscopy. Nat. Commun. 8, 14761 (2017).

    Article  Google Scholar 

  11. Kézsmárki, I. et al. Néel-type skyrmion lattice with confined orientation in the polar magnetic semiconductor GaV4S8. Nat. Mater. 14, 1116–1122 (2015).

    Article  Google Scholar 

  12. Kurumaji, T. et al. Néel-type skyrmion lattice in the tetragonal polar magnet VOSe2O5. Phys. Rev. Lett. 119, 237201 (2017).

    Article  Google Scholar 

  13. Srivastava, A. K. et al. Observation of robust Néel skyrmions in metallic PtMnGa. Adv. Mater. 32, 1904327 (2020).

    Article  CAS  Google Scholar 

  14. Hoffmann, M. et al. Antiskyrmions stabilized at interfaces by anisotropic Dzyaloshinskii–Moriya interactions. Nat. Commun. 8, 308 (2017).

    Article  Google Scholar 

  15. Camosi, L., Rougemaille, N., Fruchart, O., Vogel, J. & Rohart, S. Micromagnetics of antiskyrmions in ultrathin films. Phys. Rev. B 97, 134404 (2018).

    Article  CAS  Google Scholar 

  16. Nayak, A. K. et al. Magnetic antiskyrmions above room temperature in tetragonal Heusler materials. Nature 548, 561–566 (2017).

    Article  CAS  Google Scholar 

  17. Jena, J. et al. Observation of magnetic antiskyrmions in the low magnetization ferrimagnet Mn2Rh0.95Ir0.05Sn. Nano Lett. 20, 59–65 (2020).

    Article  CAS  Google Scholar 

  18. Gambino, R. J., McGuire, T. R. & Nakamura, Y. Magnetic properties of the iron-group metal phosphides. J. Appl. Phys. 38, 1253–1255 (1967).

    Article  CAS  Google Scholar 

  19. Goto, M., Tange, H., Tokunaga, T., Fujii, H. & Okamoto, T. Magnetic properties of the (Fe1−xMx)3P compounds. Jpn J. Appl. Phys. 16, 2175–2179 (1977).

    Article  CAS  Google Scholar 

  20. Koshibae, W. & Nagaosa, N. Theory of antiskyrmions in magnets. Nat. Commun. 7, 10542 (2016).

    Article  CAS  Google Scholar 

  21. Vir, P. et al. Tetragonal superstructure of the antiskyrmion hosting Heusler compound Mn1.4PtSn. Chem. Mater. 31, 5876–5880 (2019).

    Article  CAS  Google Scholar 

  22. Peng, L. C. et al. Controlled transformation of skyrmions and antiskyrmions in a non-centrosymmetric magnet. Nat. Nanotech. 15, 181–186 (2020).

    Article  CAS  Google Scholar 

  23. Jena, J. et al. Elliptical Bloch skyrmion chiral twins in an antiskyrmion system. Nat. Commun. 11, 1115 (2020).

    Article  Google Scholar 

  24. Kittel, C. Theory of the structure of ferromagnetic domains in films and small particles. Phys. Rev. 70, 965–971 (1946).

    Article  CAS  Google Scholar 

  25. Malozemoff, A. P. & Slonczewski, J. C. Magnetic Domain Walls in Bubble Materials (Academic, 1979).

  26. Hubert, A. & Schäfer, R. Magnetic Domains: The Analysis of Magnetic Microstructures (Springer, 1998).

  27. Szymczak, R. A modification of the Kittel open structure. J. Appl. Phys. 39, 875–876 (1968).

    Article  Google Scholar 

  28. Kaczér, J. On the domain structure of uniaxial ferromagnets. Sov. Phys. JETP 19, 1204–1208 (1964).

    Google Scholar 

  29. Gemperle, R., Murtinová, L. & Kamberský, V. Experimental verification of theoretical relations for the domain structure of uniaxial ferromagnets. Phys. Stat. Sol. A 158, 229 (1996).

    Article  CAS  Google Scholar 

  30. Szmaja, W. Investigations of the domain structure of anisotropic sintered Nd–Fe–B-based permanent magnets. J. Mag. Mag. Mater. 301, 546–561 (2006).

    Article  CAS  Google Scholar 

  31. Kreyssig, A. et al. Probing fractal magnetic domains on multiple length scales in Nd2Fe14B. Phys. Rev. Lett. 102, 047204 (2009).

    Article  CAS  Google Scholar 

  32. Jalli, J. et al. MFM studies of magnetic domain patterns in bulk barium ferrite (BaFe12O19) single crystals. J. Mag. Mag. Mater. 323, 2627–2631 (2011).

    Article  CAS  Google Scholar 

  33. Vansteenkiste, A. et al. The design and verification of MuMax3. AIP Adv. 4, 107133 (2014).

    Article  Google Scholar 

  34. Ma, T. et al. Tunable magnetic antiskyrmion size and helical period from nanometers to micrometers in a D2d Heusler compound. Adv. Mater. 32, 2002043 (2020).

    Article  CAS  Google Scholar 

  35. Ishizuka, K. & Allman, B. Phase measurement of atomic resolution image using transport of intensity equation. J. Electron Microsc. 54, 191–197 (2005).

    CAS  Google Scholar 

  36. Chapman, J. N., Batson, P. E., Waddell, E. M. & Ferrier, R. P. The direct determination of magnetic domain wall profiles by differential phase contrast electron microscopy. Ultramicroscopy 3, 203–214 (1978).

    Article  CAS  Google Scholar 

  37. Sandweg, C. W. et al. Direct observation of domain wall structures in curved permalloy wires containing an antinotch. J. Appl. Phys. 103, 093906 (2008).

    Article  Google Scholar 

  38. McGrouther, D. et al. Internal structure of hexagonal skyrmion lattices in cubic helimagnets. New J. Phys. 18, 095004 (2016).

    Article  Google Scholar 

  39. Shibata, N. et al. Direct visualization of local electromagnetic field structures by scanning transmission electron microscopy. Acc. Chem. Res. 50, 1502–1512 (2017).

    Article  CAS  Google Scholar 

  40. Matsumoto, T., So, Y. G., Kohno, Y., Ikuhara, Y. & Shibata, N. Stable magnetic skyrmion states at room temperature confined to corrals of artificial surface pits fabricated by a focused electron beam. Nano Lett. 18, 754–762 (2018).

    Article  CAS  Google Scholar 

  41. Pöllath, S. et al. Spin structure relation to phase contrast imaging of isolated magnetic Bloch and Néel skyrmions. Ultramicroscopy 212, 112973 (2020).

    Article  Google Scholar 

  42. Yasin, F. S. et al. Bloch lines constituting antiskyrmions captured via differential phase contrast. Adv. Mater. 32, 2004206 (2020).

    Article  CAS  Google Scholar 

  43. Ishizuka, A., Oka, M., Seki, T., Shibata, N. & Ishizuka, K. Boundary-artifact-free determination of potential distribution from differential phase contrast signals. Microscopy 66, 397 (2017).

    Article  Google Scholar 

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Acknowledgements

We thank N. Nagaosa, W. Koshibae, Y. Tokunaga and T. Arima for fruitful discussions. We also thank F. S. Yasin for technical support for the DPC-STEM measurement and K. Nakajima for technical support for the preparation of the FIB sample. This work was supported by JSPS Grant-in-Aids for Scientific Research (grant numbers 17K18355, 18H05225, 19H00660 and 20K15164), JST CREST (grant numbers JPMJCR1874 and JPMJCR20T1) and the Humboldt/JSPS International Research Fellow Programme (grant number 19F19815).

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Author notes

  1. These authors equally contributed: Kosuke Karube, Licong Peng.

Authors and Affiliations

  1. RIKEN Center for Emergent Matter Science (CEMS), Wako, Japan

    Kosuke Karube, Licong Peng, Jan Masell, Xiuzhen Yu, Fumitaka Kagawa, Yoshinori Tokura & Yasujiro Taguchi

  2. Department of Applied Physics, University of Tokyo, Bunkyo-ku, Japan

    Fumitaka Kagawa & Yoshinori Tokura

  3. Tokyo College, University of Tokyo, Bunkyo-ku, Japan

    Yoshinori Tokura

Authors
  1. Kosuke Karube
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Contributions

K.K., X.Y., Y. Tokura and Y. Taguchi jointly conceived the project. K.K. synthesized the bulk crystals and performed magnetization measurements. L.P. fabricated the FIB samples and performed the LTEM and DPC-STEM measurements. MFM measurements were performed by K.K. with the support of F.K. J.M. theoretically considered the experimental results and performed micromagnetic simulations. The results were discussed and interpreted by all the authors.

Corresponding authors

Correspondence to Kosuke Karube or Yasujiro Taguchi.

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The authors declare no competing interests.

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Peer review information Nature Materials thanks the anonymous reviewers for their contribution to the peer review of this work.

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Extended data

Extended Data Fig. 1 Micromagnetic simulations of the sawtooth magnetic texture.

The panels show the magnetization in various layers at different depth of a film as obtained from a three-dimensional micromagnetic simulation. The simulated sample measures 1.6 µm × 0.8 µm × 5.3 µm where periodic boundary conditions are applied in the x–y-plane to mimic an extended plate. The colour encodes the direction of the magnetization in the plane and black/white encodes the out-of-plane component, as indicated by the square-shaped antiskyrmion on the bottom right panel, which also sketches the DMI-preferred helicities. In addition, small arrows also show the direction of the in-plane components of the magnetization.

Supplementary information

Supplementary Information

Supplementary Notes 1–10, Figs. 1–7, Tables 1 and 2, and references 1–19.

Supplementary Video 1

Field-induced transformation from antiskyrmions to skyrmions.

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Karube, K., Peng, L., Masell, J. et al. Room-temperature antiskyrmions and sawtooth surface textures in a non-centrosymmetric magnet with S4 symmetry. Nat. Mater. 20, 335–340 (2021). https://doi.org/10.1038/s41563-020-00898-w

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