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arXiv · 2407.02999

Fermi Surface Nesting Driving the RKKY Interaction in the Centrosymmetric Skyrmion Magnet Gd2PdSi3

Abstract

The magnetic skyrmions generated in a centrosymmetric crystal were recently first discovered in Gd2PdSi3. In light of this, we observe the electronic structure by angle-resolved photoemission spectroscopy (ARPES) and unveil its direct relationship with the magnetism in this compound. The Fermi surface and band dispersions are demonstrated to have a good agreement with the density functional theory (DFT) calculations carried out with careful consideration of the crystal superstructure. Most importantly, we find that the three-dimensional Fermi surface has extended nesting which matches well the q-vector of the magnetic order detected by recent scattering measurements. The consistency we find among ARPES, DFT, and the scattering measurements suggests the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction involving itinerant electrons to be the formation mechanism of skyrmions in Gd2PdSi3.

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BibTeXRIS

Yuyang Dong, Yosuke Arai, Kenta Kuroda, Masayuki Ochi, Natsumi Tanaka, Yuxuan Wan, Matthew D. Watson, Timur K. Kim, Cephise Cacho, Makoto Hashimoto, Donghui Lu, Yuji Aoki, Tatsuma D. Matsuda, Takeshi Kondo. 2024-07-03. Fermi Surface Nesting Driving the RKKY Interaction in the Centrosymmetric Skyrmion Magnet Gd2PdSi3. https://doi.org/10.1103/physrevlett.133.016401

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