Mode locking between helimagnetism and ferromagnetism

Nature Physics (2026)Cite this article Non-collinear spin textures, such as spin spirals and skyrmions, exhibit rich emergent physics in their spin dynamics. Nevertheless, the potential to utilize their distinctive spin resonance characteristics for on-chip microwave magnonic applications is rarely explored. Here we demonstrate microwave emission and mode coupling from the resonating spin spiral lattice in a Cu2OSeO3/Pt/NiFe heterostructure. We use time-resolved resonant elastic X-ray scattering to visualize the exact vectorial spin precession modes from the two magnetic species in real time. Our results show that the ferromagnetic NiFe layer dynamically captures the excitation modes of the conical order in helimagnet Cu2OSeO3. The off-resonance NiFe spin precession is phase locked to the helimagnet with a fixed offset, thereby presenting distinct chiral dynamics. This demonstrates that the magnons produced in the process—referred to as helimagnons—can wirelessly transmit spin information at gigahertz frequencies, opening new avenues for on-chip microwave magnonics.This is a preview of subscription content, access via your institution Access Nature and 54 other Nature Portfolio journals Get Nature+, our best-value online-access subscription $32.99 / 30 days cancel any timeSubscribe to this journal Receive 12 print issues and online access $259.00 per yearonly $21.58 per issueBuy this articleUSD 39.95Prices may be subject to local taxes which are calculated during checkoutAll data required for assessing the conclusions are available via Zenodo at https://doi.org/10.5281/zenodo.18184389 (ref. 45). Source data are provided with this paper.The refinement algorithm for obtaining the resonating modes is available from the corresponding author upon request.Serga, A. A., Chumak, A. V. & Hillebrands, B. YIG magnonics. J. Phys. D: Appl. Phys. 43, 264002 (2010).Article ADS Google Scholar Chumak, A. V., Vasyuchka, V. I., Serga, A. A. & Hillebrands, B. Magnon spintronics. Nat. Phys. 11, 453–461 (2015).Article Google Scholar Pirro, P., Vasyuchka, V. I., Serga, A. A. & Hillebrands, B. Advances in coherent magnonics. Nat. Rev. Mater. 6, 1114 (2021).Article ADS Google Scholar Flebus, B. et al. The 2024 magnonics roadmap. J. Phys.: Condens. Matter 36, 363501 (2024).

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Zenodo https://doi.org/10.5281/zenodo.18184389 (2026).Download referencesThis work was supported by the National Key R&D Program of China (grant number 2022YFA1403602) and the National Natural Science Foundation of China (grant number 12241406). H.J. acknowledges support from the China Postdoctoral Science Foundation (grant number 2025M773358). J.C. acknowledges the Double First-Class Initiative Fund of ShanghaiTech University (2025X0201-904-01).

Diamond Light Source is acknowledged for beamtime on beamline I10 under proposal MM36751.These authors contributed equally: Jingyi Chen, Haonan Jin.School of Physical Science and Technology, ShanghaiTech University, Shanghai, ChinaJingyi Chen, Haonan Jin & Shilei ZhangShanghaiTech Laboratory for Topological Physics, ShanghaiTech University, Shanghai, ChinaHaonan Jin & Shilei ZhangDepartment of Physics, Clarendon Laboratory, University of Oxford, Oxford, UKEthan L. Arnold & Thorsten HesjedalDiamond Light Source, Harwell Science and Innovation Campus, Didcot, UKEthan L. Arnold & Gerrit van der LaanCenter for Transformative Science, ShanghaiTech University, Shanghai, ChinaShilei ZhangSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarS.Z. conceived of and supervised the project. J.C., H.J., E.L.A., G.v.d.L., T.H. and S.Z. performed the experiments and analysed the data. S.Z. wrote the paper with input from all authors. All authors discussed the results and contents of the paper.Correspondence to Shilei Zhang.The authors declare no competing interests.Nature Physics thanks the anonymous reviewers for their contribution to the peer review of this work.Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.A phase-modulated 500 MHz reference is delayed, frequency-multiplied, and delivered to the sample, while the scattered x-ray signal is detected with photodiode lock-in referencing.The procedure starts from initial angles obtained from micromagnetic simulations and iteratively updates the four-angle model to minimize the residual between calculated and experimental profiles.∣χ∣ is separately calculated for Cu2OSeO3 in (a) and NiFe in (b), respectively. Both the +Q and −Q modes are imprinted onto the NiFe layer. The plots in the insets show line cuts through the +Q mode.Source dataSupplementary Sections 1–7 and Figs. 1–14.Dynamical mode communication between the resonating conical spins and the pick-up NiFe spins.Statistical source data.Statistical source data.Statistical source data.Statistical source data.Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.Reprints and permissionsChen, J., Jin, H., Arnold, E.L. et al. Mode locking between helimagnetism and ferromagnetism. Nat. Phys. (2026). https://doi.org/10.1038/s41567-025-03148-5Download citationReceived: 04 September 2024Accepted: 25 November 2025Published: 28 January 2026Version of record: 28 January 2026DOI: https://doi.org/10.1038/s41567-025-03148-5Anyone you share the following link with will be able to read this content:Sorry, a shareable link is not currently available for this article. Provided by the Springer Nature SharedIt content-sharing initiative