Eigenmodes of magnetic skyrmion lattices - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Physical Review B Année : 2023

Eigenmodes of magnetic skyrmion lattices

Louise Desplat
Bertrand Dupé

Résumé

We explore the interplay between topology and eigenmodes by changing the stabilizing mechanism of skyrmion lattices (skX). We focus on two prototypical ultrathin films hosting a hexagonal [Pd/Fe/Ir(111)] and a square [Fe/Ir(111)] skyrmion lattice, which can both be described by an extended Heisenberg Hamiltonian. We first examine whether the Dzyaloshinkskii-Moriya, or the exchange interaction as the leading energy term affects the modes of the hexagonal skX of Pd/Fe/Ir(111). In all cases, we find that the lowest-frequency modes correspond to internal degrees of freedom of individual skyrmions, and suggest a classification based on azimuthal and radial numbers (l, p), with up to l = 6 and p = 2. We also show that the gyration behavior induced by an in-plane field corresponds to the excitation of l = 1 deformation modes with varying radial numbers. Second, we examine the square lattice of skyrmions of Fe/Ir(111). Its stabilization mechanism is dominated by the four-spin interaction. After relaxation, the unit cell does not carry a topological charge, and the eigenmodes do not correspond to internal skyrmion deformations. By reducing the four-spin interaction, the integer topological charge is recovered, but the charge carriers do not possess internal degrees of freedom, nor are they separated by energy barriers. We conclude that a four-spin dominated Hamiltonian does not yield skyrmion lattice solutions and that, therefore, a nontrivial topology does not imply the existence of skyrmions.
Fichier principal
Vignette du fichier
PhysRevB.107.144415.pdf (4.63 Mo) Télécharger le fichier
Origine Fichiers éditeurs autorisés sur une archive ouverte

Dates et versions

hal-04444305 , version 1 (07-02-2024)

Identifiants

Citer

Louise Desplat, Bertrand Dupé. Eigenmodes of magnetic skyrmion lattices. Physical Review B, 2023, 107 (14), pp.144415. ⟨10.1103/PhysRevB.107.144415⟩. ⟨hal-04444305⟩
2 Consultations
20 Téléchargements

Altmetric

Partager

Gmail Mastodon Facebook X LinkedIn More