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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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.
The authors declare no competing financial interests.
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Schwarze, T., Waizner, J., Garst, M. et al. Universal helimagnon and skyrmion excitations in metallic, semiconducting and insulating chiral magnets. Nature Mater 14, 478–483 (2015). https://doi.org/10.1038/nmat4223
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