Abstract

The possibility of utilizing the rich spin-dependent properties of graphene has attracted much attention in the pursuit of spintronics advances. The promise of high-speed and low-energy-consumption devices motivates the search for layered structures that stabilize chiral spin textures such as topologically protected skyrmions. Here we demonstrate that chiral spin textures are induced at graphene/ferromagnetic metal interfaces. Graphene is a weak spin–orbit coupling material and is generally not expected to induce a sufficient Dzyaloshinskii–Moriya interaction to affect magnetic chirality. We demonstrate that indeed graphene does induce a type of Dzyaloshinskii–Moriya interaction due to the Rashba effect. First-principles calculations and experiments using spin-polarized electron microscopy show that this graphene-induced Dzyaloshinskii–Moriya interaction can have a similar magnitude to that at interfaces with heavy metals. This work paves a path towards two-dimensional-material-based spin–orbitronics.

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Acknowledgements

This work was supported by the European Union's Horizon 2020 Research and Innovation Programme under grant agreement no. 696656 (GRAPHENE FLAGSHIP), the ANR ULTRASKY, SOSPIN. Ab initio calculations used the resources of GENCI-CINES with grant no. C2016097605. Work at the Molecular Foundry was supported by the Office of Science, Office of Basic Energy Sciences, of the US Department of Energy under contract no. DE-AC02-05CH11231. Work at UCD was supported by the UC Office of the President Multicampus Research Programs and Initiatives MRP-17-454963 (G.C.) and NSF DMR-1610060 (K.L.). A.A.C.C., W.A.A.M. and E.A.S. acknowledge the support of the Brazilian agencies CAPES, CNPq and FAPEMIG. H.Y. would like also to acknowledge the 1000 Talents Program for Young Scientists of China and Ningbo 3315 Program. We thank V. Cros, O. Boulle, G. Gaudin, I. M. Miron, T. P. Ma and A. Thiaville for fruitful discussions and comments.

Author information

Author notes

    • Alexandre A. C. Cotta

    Present address: Departamento de Física, Universidade Federal de Lavras, Lavras, Brazil

  1. These authors contributed equally: Hongxin Yang, Gong Chen.

Affiliations

  1. Univ. Grenoble Alpes, CEA, CNRS, Grenoble INP, INAC-SPINTEC, Grenoble, France

    • Hongxin Yang
    • , Sergey A. Nikolaev
    •  & Mairbek Chshiev
  2. Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, Palaiseau, France

    • Hongxin Yang
    •  & Albert Fert
  3. Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, China

    • Hongxin Yang
  4. NCEM, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, USA

    • Gong Chen
    • , Alexandre A. C. Cotta
    • , Alpha T. N’Diaye
    •  & Andreas K. Schmid
  5. Department of Physics, University of California, Davis, CA, USA

    • Gong Chen
    •  & Kai Liu
  6. Centro de Desenvolvimento da Tecnologia Nuclear, CDTN, Belo Horizonte, Brazil

    • Alexandre A. C. Cotta
    •  & Waldemar A. A. Macedo
  7. Departamento de Física, ICEx, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil

    • Alexandre A. C. Cotta
    •  & Edmar A. Soares

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Contributions

H.Y. and G.C. conceived the study. H.Y and S.A.N. performed the ab initio calculations with the help of M.C. H.Y., M.C., S.A.N. and A.F. analysed and interpreted the ab initio results. G.C. and A.A.C.C. carried out the SPLEEM measurements. A.K.S. supervised the SPLEEM facility. G.C., A.A.C.C., A.T.N., K.L. and A.K.S analysed the SPLEEM results. G.C. derived the DMI strength from experimental data. G.C., A.A.C.C., A.T.N., K.L., A.K.S., E.A.S. and W.A.A.M. interpreted and discussed the experimental result. A.A.C.C., E.A.S. and W.A.A.M. performed XPS measurements. H.Y and G.C. prepared the manuscript with help from A.A.C.C., A.K.S., S.A.N. and M.C. All authors commented on the manuscript.

Competing interests

The authors declare that they have no competing interests.

Corresponding authors

Correspondence to Hongxin Yang or Gong Chen or Andreas K. Schmid or Mairbek Chshiev.

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https://doi.org/10.1038/s41563-018-0079-4