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The concertina pattern

From micromagnetics to domain theory
  • Felix Otto
  • Jutta Steiner
Article

Abstract

This is a continuation of a series of papers on the concertina pattern. The concertina pattern is a ubiquitous metastable, nearly periodic magnetization pattern in elongated thin film elements. In previous papers, a reduced variational model for this pattern was rigorously derived from 3-d micromagnetics. Numerical simulations of the reduced model reproduce the concertina pattern and show that its optimal period \({\widehat{w}_{opt}}\) is an increasing function of the applied external field \({\widehat{h}_{ext}}\) . The latter is an explanation of the experimentally observed coarsening. Domain theory, which can be heuristically derived from the reduced model, predicts and quantifies this dependence of \({\widehat{w}_{opt}}\) on \({\widehat{h}_{ext}}\) . In this paper, we rigorously extract these heuristic observations of domain theory directly from the reduced model. The main ingredient of the analysis is a new type of estimate on solutions of a perturbed Burgers equation.

Mathematics Subject Classification (2000)

78A99 49K20 74G60 

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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  1. 1.Institute for Applied MathematicsUniversity of BonnBonnGermany

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