Computational Micromagnetism of Magnetic Structures and Magnetization Processes in Thin Platelets and Small Particles

  • H. Kronmüller
  • R. Hertel
Part of the NATO Science Series book series (NAII, volume 41)


The micromagnetic background for the investigation of magnetic configurations in thin platelets and small particles by means of the Finite Element Method is discussed. It is shown that in thin rectangular platelets high remanence and low remanence configurations may exist.

The configurations of lowest magnetic energy are the Landau structure with cross-tie wall and the diamond structure. The magnetization process of these configurations takes place by reversible spin rotations and domain wall displacements. Intrinsic irreversible magnetization processes are related to the annihilation of domain walls and the displacement of the domain walls to the particle edges. The coercive field is found to correspond approximately to the demagnetization field of the homogeneously magnetized platelet.

In cubic particles it is shown that with increasing edge length the configurations with lowest energy change from the so-called Flower State via the Twisted Flower State to the Vortex State. For a composite system of hard and soft magnetic particles the hysteresis loops and the coercive fields are determined in dependence of the diameter of the soft particle. It turns out that the magnetically soft particles reduce the coercive field of the hard phase for diameters > 2.5 ͔B of the hard phase.


Domain Wall Coercive Field Soft Particle Closure Domain Magnetization Process 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media Dordrecht 2001

Authors and Affiliations

  • H. Kronmüller
    • 1
  • R. Hertel
    • 1
  1. 1.Max-Planck-Institut für MetallforschungStuttgartGermany

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