Hybrid FEM-BEM Approach for Two- and Three-Dimensional Open Boundary Magnetostatic Problems

A.Weddemann[1], D. Kappe[2], and A. Hütten[2]
[1]Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge MA, USA
[2]Department of Physics, Thin Films and Physics of Nanostructures, Bielefeld University, Bielefeld, Germany

In principal, the calculation of the magnetic state inside a magnetic object requires the evaluation of the field in the entire unbounded space. With finite element methods restricted to finite domains, commonly auxiliary domains are employed which result in a non-physical cut-off. Not only are these additional domains result in an increased number of degrees of freedom which are strictly speaking not of interest, the artificial boundaries also affect the solution.

In order to restrict the calculation to the domains of interest, we implement an open boundary method based on a hybrid FEM-BEM approach which is tested for fully three-dimensional systems and geometries of high aspect ratios.