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arXiv · 2212.12280

Quantum oscillations in a centrosymmetric skyrmion-hosting magnet GdRu2Si2

N. Matsuyama·T. Nomura·S. Imajo·T. Nomoto·R. Arita·K. Sudo·M. Kimata·N. D. Khanh·R. Takagi·Y. Tokura·S. Seki·K. Kindo·Y. Kohama
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Abstract

We have performed magnetic torque and resistivity measurements on a centrosymmetric skyrmion-host GdRu2Si2, in which the dominant magnetic interaction leading to skyrmion formation is under debate. We observe both the de Haas-van Alphen and Shubnikov-de Haas oscillations in the forced ferromagnetic phase. The angular dependence of the quantum oscillation frequencies can be reproduced by the ab-initio calculation. The de Haas-van Alphen oscillation is also observed in the double-Q phase with a different frequency to that in the forced ferromagnetic phase, indicating a Fermi surface reconstruction due to the coupling between localized spins and conduction electrons. Based on these experimental findings, the magnetic interactions in this system are discussed.

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N. Matsuyama, T. Nomura, S. Imajo, T. Nomoto, R. Arita, K. Sudo, M. Kimata, N. D. Khanh, R. Takagi, Y. Tokura, S. Seki, K. Kindo, Y. Kohama. 2022-12-23. Quantum oscillations in a centrosymmetric skyrmion-hosting magnet GdRu2Si2. https://doi.org/10.1103/physrevb.107.104421

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