Letter | Published:

Universal helimagnon and skyrmion excitations in metallic, semiconducting and insulating chiral magnets

Nature Materials volume 14, pages 478483 (2015) | Download Citation

Abstract

Nearly seven decades of research on microwave excitations of magnetic materials have led to a wide range of applications in electronics1,2,3,4. The recent discovery of topological spin solitons in chiral magnets, so-called skyrmions5,6,7,8,9, promises high-frequency devices that exploit the exceptional emergent electrodynamics of these compounds10,11,12,13,14. Therefore, an accurate and unified quantitative account of their resonant response is key. Here, we report all-electrical spectroscopy of the collective spin excitations in the metallic, semiconducting and insulating chiral magnets MnSi, Fe1−xCoxSi and Cu2OSeO3, respectively, using broadband coplanar waveguides. By taking into account dipolar interactions, we achieve a precise quantitative modelling across the entire magnetic phase diagrams using two material-specific parameters that quantify the chiral and the critical field energy. The universal behaviour sets the stage for purpose-designed applications based on the resonant response of chiral magnets with tailored electric conductivity and an unprecedented freedom for an integration with electronics.

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Acknowledgements

We wish to thank P. Böni, K. Everschor, M. Mochizuki, N. Nagaosa, S. Mayr and, in particular, A. Rosch for helpful discussions and support. A.B. acknowledges financial support through the TUM Graduate School. Financial support through DFG TRR80, SFB608, German Excellence Cluster Nanosystems Initiative Munich, and ERC-AdG (291079 TOPFIT) is gratefully acknowledged.

Author information

Affiliations

  1. Lehrstuhl für Physik funktionaler Schichtsysteme, Technische Universität München, Physik Department, D-85748 Garching, Germany

    • T. Schwarze
    • , I. Stasinopoulos
    •  & D. Grundler
  2. Institute of Theoretical Physics, University of Cologne, D-50937 Cologne, Germany

    • J. Waizner
    •  & M. Garst
  3. Lehrstuhl für Topologie korrelierter Systeme, Technische Universität München, Physik Department, D-85748 Garching, Germany

    • A. Bauer
    •  & C. Pfleiderer
  4. Institut de Physique de la Matiére Complexe, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland

    • H. Berger
  5. Institut des Matériaux, Faculté Sciences et Technique de l’Ingénieur, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland

    • D. Grundler

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Contributions

T.S. and D.G. developed the experimental set-up and performed the experiments; T.S., J.W., M.G., A.B. and I.S. analysed the experimental data; A.B. grew the MnSi and Fe1−xCoxSi single crystals and characterized them; H.B. grew the Cu2OSeO3 single crystals and characterized them; J.W. and M.G. developed the theoretical interpretation; D.G. supervised the experimental work; D.G. and C.P. proposed this study; T.S., A.B., M.G., C.P. and D.G. wrote the manuscript; all authors discussed the data and commented on the manuscript.

Competing interests

The authors declare no competing financial interests.

Corresponding authors

Correspondence to M. Garst or D. Grundler.

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https://doi.org/10.1038/nmat4223

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