We have performed magnetic torque and resistivity measurements on the centrosymmetric skyrmion host ${\mathrm{GdRu}}_2{\mathrm{Si}}_2$, 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 an ab initio calculation. The de Haas–van Alphen oscillation is also observed in the double-$\mathbf{Q}$ phase with a frequency different from 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.

• Received 26 December 2022
• Accepted 6 March 2023

DOI:https://doi.org/10.1103/PhysRevB.107.104421