Onset of pattern formation in thin ferromagnetic films with perpendicular anisotropy

We consider the onset of pattern formation in an ultrathin ferromagnetic film of the form Ωt:=Ω×[0,t] for Ω⋐R2 with preferred perpendicular magnetization direction. The relative micromagnetic energy is given by E[M]=∫Ωtd2|∇M|2+Q∫Ωt(M21+M22)+∫R3|H(M)|2−∫R3|H(e3χΩt)|2, describing the energy difference...

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Hauptverfasser: Brietzke, Birger (VerfasserIn) , Knüpfer, Hans (VerfasserIn)
Dokumenttyp: Article (Journal)
Sprache:Englisch
Veröffentlicht: 06 April 2023
In: Calculus of variations and partial differential equations
Year: 2023, Jahrgang: 62, Heft: 4, Pages: 1-22
ISSN:1432-0835
DOI:10.1007/s00526-023-02459-w
Online-Zugang:Verlag, kostenfrei, Volltext: https://doi.org/10.1007/s00526-023-02459-w
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Verfasserangaben:Birger Brietzke, Hans Knüpfer
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Zusammenfassung:We consider the onset of pattern formation in an ultrathin ferromagnetic film of the form Ωt:=Ω×[0,t] for Ω⋐R2 with preferred perpendicular magnetization direction. The relative micromagnetic energy is given by E[M]=∫Ωtd2|∇M|2+Q∫Ωt(M21+M22)+∫R3|H(M)|2−∫R3|H(e3χΩt)|2, describing the energy difference for a given magnetization M:R3→R3 with |M|=χΩt and the uniform magnetization e3χΩt. For t≪d, we derive the scaling of the minimal energy and a BV-bound in the critical regime, where the base area of the film has size of order |Ω|12∼(Q−1)−12de2πdtQ−1√. We furthermore investigate the onset of non-trivial pattern formation in the critical regime depending on the size of the rescaled film.
Beschreibung:Gesehen am 16.05.2023
Beschreibung:Online Resource
ISSN:1432-0835
DOI:10.1007/s00526-023-02459-w