A finite elements model including surface contribution in micromagnetic simulation

• The magnetic peculiarities of the surface are introduced by a different set of PDE.
• Detailed 3-D meshing at the surface layer is not needed.
• Simulations for small particles agree with experimentally observed behavior.
• For big particles, the surface governs only the growth of the magnetic domains.

This work presents micromagnetic simulations of the behavior of ferromagnetic particles, carried out by use of the finite element method, taking into account, in a special way, the peculiarity of the surface. Results including the role of the surface in the various mechanisms of magnetization reversal, like the coherent rotation, the vortex creation and the nucleation/expansion of magnetic domains, as dictated by the magnitude of the particles, are presented and commented upon.