Magnetic skyrmions under confinement

Monteil, A; Muratov, C.B.; Simon, T.M.; Slastikov, V.V.

Forschungsartikel (Zeitschrift) | Peer reviewed

Zusammenfassung

We present a variational treatment of confined magnetic skyrmions in a minimal micromag- netic model of ultrathin ferromagnetic films with interfacial Dzylashinksii-Moriya interaction (DMI) in competition with the exchange energy, with a possible addition of perpendicular mag- netic anisotropy. Under Dirichlet boundary conditions that are motivated by the asymptotic treatment of the stray field energy in the thin film limit we prove existence of topologically non-trivial energy minimizers that concentrate on points in the domain as the DMI strength parameter tends to zero. Furthermore, we derive the leading order non-trivial term in the Γ- expansion of the energy in the limit of vanishing DMI strength that allows us to completely characterize the limiting magnetization profiles and interpret them as particle-like states whose radius and position are determined by minimizing a renormalized energy functional. In particular, we show that in our setting the skyrmions are strongly repelled from the domain boundaries, which imparts them with stability that is highly desirable for applications. We provide explicit calculations of the renormalized energy for a number of basic domain geometries.

Details zur Publikation

FachzeitschriftCommunications in Mathematical Physics (Commun. Math. Phys.)
Jahrgang / Bandnr. / Volume404
Seitenbereich1571-1605
StatusVeröffentlicht
Veröffentlichungsjahr2023
Sprache, in der die Publikation verfasst istEnglisch
DOI10.1007/s00220-023-04864-w
StichwörterMicromagnetics; Skyrmions; Dzyaloshinskii-Moriya interaction; Gamma-convergence

Autor*innen der Universität Münster

Simon, Theresa
Juniorprofessur für Angewandte Mathematik (Prof. Simon)