Abstract

The well-known Hall effect describes the transverse deflection of charged particles (electrons/holes) as a result of the Lorentz force. Similarly, it is intriguing to examine if quasi-particles without an electric charge, but with a topological charge, show related transverse motion. Magnetic skyrmions with a well-defined spin texture with a unit topological charge serve as good candidates to test this hypothesis. In spite of the recent progress made on investigating magnetic skyrmions, direct observation of the skyrmion Hall effect has remained elusive. Here, by using a current-induced spin Hall spin torque, we experimentally demonstrate the skyrmion Hall effect, and the resultant skyrmion accumulation, by driving skyrmions from the creep-motion regime (where their dynamics are influenced by pinning defects) into the steady-flow-motion regime. The experimental observation of transverse transport of skyrmions due to topological charge may potentially create many exciting opportunities, such as topological selection.

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Acknowledgements

Work carried out at the Argonne National Laboratory including lithographic processing and MOKE imaging was supported by the US Department of Energy, Office of Science, Basic Energy Sciences, Materials Science and Engineering Division. Lithography was carried out at the Center for Nanoscale Materials, which is supported by the DOE, Office of Science, Basic Energy Sciences under Contract No. DE-AC02-06CH11357. W.J. was partially supported by the 1000-Youth Talent Program of China, and National Key Research Plan of China under contract number 2016YFA0302300. Thin film growth performed at UCLA was partially supported by the NSF Nanosystems Engineering Research Center for Translational Applications of Nanoscale Multiferroic Systems (TANMS). Y.Z. acknowledges support by the National Natural Science Foundation of China (Project No. 1157040329), Shenzhen Fundamental Research Fund under Grant No. JCYJ20160331164412545. X.Z. was supported by JSPS RONPAKU (Dissertation Ph.D.) Program. Work at Bryn Mawr College is supported by NSF CAREER award (No. 1053854). The authors wish to thank C. Reichhardt for insightful discussions.

Author information

Author notes

    • Wanjun Jiang
    •  & Xichao Zhang

    These authors contributed equally to this work.

Affiliations

  1. Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439, USA

    • Wanjun Jiang
    • , Wei Zhang
    • , M. Benjamin Jungfleisch
    • , John E. Pearson
    • , Olle Heinonen
    • , Axel Hoffmann
    •  & Suzanne G. E. te Velthuis
  2. State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China

    • Wanjun Jiang
  3. Collaborative Innovation Center of Quantum Matter, Beijing 100084, China

    • Wanjun Jiang
  4. School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen 518172, China

    • Xichao Zhang
    •  & Yan Zhou
  5. Department of Electric Engineering, University of California, Los Angeles, California 90095, USA

    • Guoqiang Yu
    •  & Kang L. Wang
  6. Department of Physics, Oakland University, Rochester, Michigan 48309, USA

    • Wei Zhang
  7. Department of Physics, Bryn Mawr College, Bryn Mawr, Pennsylvania 19010, USA

    • Xiao Wang
    •  & Xuemei Cheng
  8. Northwestern-Argonne Institute of Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA

    • Olle Heinonen

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Contributions

W.J., A.H. and S.G.E.t.V. conceived and designed the experiments. G.Y. and K.L.W. fabricated the thin film. W.J., W.Z., X.W., M.B.J. and J.E.P., performed lithographic processing. X.Z., Y.Z. and O.H. performed micromagnetic simulation. W.J., X.W. and X.C. performed MOKE experiments and data analysis. W.J., A.H. and S.G.E.t.V. wrote the manuscript. All authors commented on the manuscript.

Competing interests

The authors declare no competing financial interests.

Corresponding authors

Correspondence to Wanjun Jiang or Axel Hoffmann or Suzanne G. E. te Velthuis.

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DOI

https://doi.org/10.1038/nphys3883

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