Abstract
We focus on a special type of domain wall appearing in the Landau–Lifshitz theory for soft ferromagnetic films. These domain walls are divergence-free \({\mathbb{S}^2}\)-valued transition layers that connect two directions \({m_\theta^\pm \in \mathbb{S}^2}\) (differing by an angle \({2\theta}\)) and minimize the Dirichlet energy. Our main result is the rigorous derivation of the asymptotic structure and energy of such “asymmetric” domain walls in the limit \({\theta \downarrow 0}\). As an application, we deduce that a supercritical bifurcation causes the transition from symmetric to asymmetric walls in the full micromagnetic model.
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References
Anzellotti G., Baldo S.: Asymptotic development by \({\Gamma}\)-convergence. Appl. Math. Optim. 27(2), 105–123 (1993)
Arnol’d, V.I.: Ordinary differential equations. Springer Textbook. Springer, Berlin, 1992. (Translated from the third Russian edition by Roger Cooke)
Berkov D.V., Ramstöck K., Hubert A.: Solving micromagnetic problems. Towards an optimal numerical method. Phys. Status Solidi (a) 137(1), 207–225 (1993)
Bethuel, F., Brezis, H., Hélein, F.: Ginzburg–Landau Vortices. Springer, Berlin, 1994
Boutet de Monvel-Berthier, A., Georgescu, V., Purice, R.: A boundary value problem related to the Ginzburg–Landau model. Commun. Math. Phys. 142(1), 1–23 (1991)
Braides A., Truskinovsky L.: Asymptotic expansions by \({\Gamma}\)-convergence. Contin. Mech. Thermodyn. 20(1), 21–62 (2008)
Brezis, H., Nirenberg, L.: Degree theory and BMO. I. Compact manifolds without boundaries. Sel. Math. (N. S.) 1(2), 197–263 (1995)
Dacorogna, B.: Direct methods in the calculus of variations. Applied Mathematical Sciences. Springer, Berlin, 2007
DeSimone A., Knüpfer H., Otto F.: 2-D stability of the Néel wall. Calc. Var. Partial Differ. Equ. 27(2), 233–253 (2006)
DeSimone, A., Kohn, R.V., Müller, S., Otto, F.: Repulsive interaction of Néel walls, and the internal length scale of the cross-tie wall. Multiscale Model. Simul. 1(1), 57–104 (2003)
Döring L., Ignat R., Otto F.: A reduced model for domain walls in soft ferromagnetic films at the cross-over from symmetric to asymmetric wall types. J. Eur. Math. Soc. (JEMS) 16(7), 1377–1422 (2014)
Evans, L.C.: Partial differential equations. Graduate Studies in Mathematics, Vol. 19, 2nd edn. American Mathematical Society, Providence, 2010
Hardy G.: Note on a theorem of hilbert. Math. Z. 6(3), 314–317 (1920)
Hubert A.: Stray-field-free magnetization configurations. Phys. Status Solidi. B Basic Res. 32(2), 519–534 (1969)
Hubert, A., Schäfer, R.: Magnetic Domains—The Analysis of Magnetic Microstructures, 1st edn. Springer, Berlin, 1998
Ignat, R.: A \({\Gamma}\)-convergence result for Néel walls in micromagnetics. Calc. Var. Partial Differ. Equ. 36(2), 285–316 (2009)
Ignat R., Otto F.: A compactness result in thin-film micromagnetics and the optimality of the Néel wall. J. Eur. Math. Soc. (JEMS) 10(4), 909–956 (2008)
Kurzke, M., Melcher, C., Moser, R., Spirn, D.: Vortex dynamics in the presence of excess energy for the Landau–Lifshitz-Gilbert equation. Calc. Var. Partial Differ. Equ. 49(3-4), 1019–1043, (2014)
LaBonte A.E.: Two-dimensional bloch-type domain walls in ferromagnetic films. J. Appl. Phys. 40(6), 2450–2458 (1969)
Lions, P.-L.: Generalized solutions of Hamilton–Jacobi equations. Research Notes in Mathematics, Vol. 69. Pitman (Advanced Publishing Program), Boston, 1982
Melcher C.: The logarithmic tail of Néel walls. Arch. Ration. Mech. Anal. 168(2), 83–113 (2003)
Melcher C.: Logarithmic lower bounds for Néel walls. Calc. Var. Partial Differ. Equ. 21(2), 209–219 (2004)
Nirenberg, L.: Topics in Nonlinear Functional Analysis, Vol. 6. American Mathematical Soc., Providence, 1974
Otto, F.: Cross-over in scaling laws: a simple example from micromagnetics. Proceedings of the International Congress of Mathematicians (Beijing, 2002), Vol. III, pp. 829–838. Higher Ed. Press, Beijing, 2002
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Döring, L., Ignat, R. Asymmetric Domain Walls of Small Angle in Soft Ferromagnetic Films. Arch Rational Mech Anal 220, 889–936 (2016). https://doi.org/10.1007/s00205-015-0944-0
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DOI: https://doi.org/10.1007/s00205-015-0944-0