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Additive interfacial chiral interaction in multilayers for stabilization of small individual skyrmions at room temperature

An Erratum to this article was published on 03 August 2016

This article has been updated

Abstract

Facing the ever-growing demand for data storage will most probably require a new paradigm. Nanoscale magnetic skyrmions are anticipated to solve this issue as they are arguably the smallest spin textures in magnetic thin films in nature. We designed cobalt-based multilayered thin films in which the cobalt layer is sandwiched between two heavy metals and so provides additive interfacial Dzyaloshinskii–Moriya interactions (DMIs), which reach a value close to 2 mJ m–2 in the case of the Ir|Co|Pt asymmetric multilayers. Using a magnetization-sensitive scanning X-ray transmission microscopy technique, we imaged small magnetic domains at very low fields in these multilayers. The study of their behaviour in a perpendicular magnetic field allows us to conclude that they are actually magnetic skyrmions stabilized by the large DMI. This discovery of stable sub-100 nm individual skyrmions at room temperature in a technologically relevant material opens the way for device applications in the near future.

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Figure 1: Interfacial DMI in asymmetric magnetic multilayers.
Figure 2: Skyrmion diameter as a function of the external out-of-plane magnetic field H.
Figure 3: Micromagnetic simulations and experimental measurements of mean domain-width evolution with DMI after demagnetization.
Figure 4: Evolution of the skyrmion size in patterned nanoscale disks and tracks.

Change history

  • 23 March 2016

    In the version of this Article originally published online, in the equation 'W = (1/4π) ∫ s · (∂xsys) dxdy', the symbol for the vector product was missing. In refs 5 and 39 the author name should have read 'Braun, H. B.'. These errors have been corrected in all versions of the Article.

  • 20 July 2016

    In the version of this Article originally published, the equation 'W = (1/4π) ∫ s · (∂xs × ∂ys) dxdy' was missing the symbol for the vector product and the first erratum did not correct the problem. Further, unrelated, changes were also required: in the sentence beginning 'We present next the micromagnetic simulations…', 'ten' should have been 'eleven', and in the sentence beginning 'With the smallest exchange constant…', '1.6 pJ m–1' should have read '1.6 mJ m–2'. All of these errors have now been corrected in the online versions of the Article.

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Acknowledgements

The authors acknowledge B. Sarafimov and M. Bechtel for their technical support at the SLS and Bessy II beamlines. The STXM experiments were performed using the X07DA (PolLux) beamline at the SLS, Paul Scherrer Institüt, Villigen, Switzerland and the Maxymus beamline BESSY II, Adlershof, Germany. The authors acknowledge financial support from the Agence Nationale de la Recherche project ANR-14-CE26-0012 ULTRASKY and from European Union grant MAGicSky No. FET-Open-665095.

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Contributions

N.R., C.M., V.C. and A.F. conceived the project. C.D. and C.M.L. grew the films. C.A.F.V., K.G. and N.R. patterned the samples. C.M., C.M.L., N.R., J.S., N.V.H., C.A.F.V., K.B., P.Wa., P.Wo, M.W., J.R. and V.C. acquired the data at the synchrotrons. C.M.L. and N.R. treated and analysed the data with the help of C.M., P. Wa., and V.C. C.M.L., J.S. and N.R. performed the micromagnetic simulations. C.M.L., N.R., V.C. and A.F. prepared the manuscript. All authors discussed and commented the manuscript.

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Correspondence to C. Moutafis, N. Reyren or V. Cros.

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Moreau-Luchaire, C., Moutafis, C., Reyren, N. et al. Additive interfacial chiral interaction in multilayers for stabilization of small individual skyrmions at room temperature. Nature Nanotech 11, 444–448 (2016). https://doi.org/10.1038/nnano.2015.313

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