The study of the shape anisotropy in patterned permalloy films

In this paper a systematic ferromagnetic resonance study shows that an in-planemagnetic anisotropy in the patterned micron octagonpermalloy (Ni$_{80}$Fe$_{20})$ elements is mainly determined by the elementgeometry. The easy-axis is along the edge of the elements, and the hard-axisis along the diagonal. The shape anisotropy of the octagon elements isdetermined by square and equilateral octagon, and the theoretical calculationwas studied on the shape anisotropy. The shape anisotropyof rectangular was calculated by using the same theory.