Abstract
Topological swirling spin textures, such as skyrmions and merons, have recently attracted much attention as potential building blocks for high-density magnetic information devices. Controlling the transformation between different types of these quasiparticles is an important challenge. To date, these transitions have mostly been limited to a few non-centrosymmetric systems, where they are driven by the Dzyaloshinskii–Moriya interaction. Here we demonstrate multistep topological transitions among a variety of meron and skyrmion crystal states in a centrosymmetric magnet GdRu2Ge2. These are governed by the competition between Ruderman–Kittel–Kasuya–Yosida interactions at inequivalent wave vectors. These findings demonstrate that even a simple centrosymmetric magnet with competing interactions can be a promising material platform to realize a richer variety of magnetic quasiparticles with distinctive symmetry and topology, whose stability can be tuned by various external stimuli.
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Acknowledgements
We thank Y. Motome, A. Kikkawa, X. Z. Yu, N. Shibata, T. Seki and S. Toyama for enlightening discussions and experimental helps. This work was partly supported by Grants-In-Aid for Scientific Research (grant nos 18H03685, 20H00349, 21H04440, 21H04990, 21K13876, 21K18595, 22H04965, 22H04468, 22KJ1061, 23K13069 and 23H04869) from JSPS, PRESTO (grant nos JPMJPR18L5, JPMJPR20B4, JPMJPR20L8) and CREST (grant no. JPMJCR1874, JPMJCR23O4) from JST, Katsu Research Encouragement Award and UTEC-UTokyo FSI Research Grant Program of the University of Tokyo, Asahi Glass Foundation and Murata Science Foundation. This work is based on experiments performed at Materials and Life Science Experimental Facility (MLF) in the Japan Proton Accelerator Research Complex (J-PARC) (Proposal No. 2020S01) and Photon Factory in High Energy Accelerator Research Organization (Proposal No. 2020G665). The illustration of crystal structure was drawn by VESTA49.
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S.S. and R.T. conceived the project. H.Y. and R.T. grew single crystals and characterized the magnetic and transport properties with the assistance of S.S., N.D.K. and Y.T. RXS measurements were carried out by H.Y., R.T., J.J. and T.N. with the assistance of H. Saito, H. Sagayama, H.N. and T.A. Neutron scattering measurements were carried out by J.J., H. Saito., S.I. and T.N. Theoretical simulation was performed by S.H. The manuscript was written by H.Y. and S.S. with the assistance of S.H. and T.N. All the authors discussed the results and commented on the manuscript.
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Yoshimochi, H., Takagi, R., Ju, J. et al. Multistep topological transitions among meron and skyrmion crystals in a centrosymmetric magnet. Nat. Phys. (2024). https://doi.org/10.1038/s41567-024-02445-9
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DOI: https://doi.org/10.1038/s41567-024-02445-9
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