Fermi-Surface Origin of Skyrmion Lattices in Centrosymmetric Rare-Earth Intermetallics

• Main Authors: Blügel, S. (Author), Bouaziz, J. (Author), Mendive-Tapia, E. (Author), Staunton, J.B (Author)
• Format: Article
• Language: English
• Published: American Physical Society 2022
• Subjects: Atomistics; Centrosymmetric; Fermi surface; Fermi surface nesting; First principles; Gadolinium compounds; Ground state; Intermetallics; Intermetallics compounds; Palladium compounds; Rare earths; Rare earths intermetallics; Ruderman-Kittel-Kasuya-Yosida; Ruthenium compounds; Shaped structures; Silicon; Silicon compounds; Skyrmion lattices; Two-dimensional
• Online Access: View Fulltext in Publisher

 We show from first principles that barrel-shaped structures within the Fermi surface of the centrosymmetric intermetallic compounds GdRu2Si2 and Gd2PdSi3 give rise to Fermi surface nesting, which determines the strength and sign of quasi-two-dimensional Ruderman-Kittel-Kasuya-Yosida pairwise exchange interactions between the Gd moments. This is the principal mechanism leading to their helical single-q spin-spiral ground states, providing transition temperatures and magnetic periods in good agreement with experiment. Using atomistic spin-dynamic simulations, we draw a direct line between the subtleties of the three-dimensional Fermi surface topology and the stabilization of a square skyrmion lattice in GdRu2Si2 at applied magnetic fields as observed in experiment. © 2022 American Physical Society.