Micromagnetic simulation of 90° domain walls in thin iron films

Abstract
The micromagnetic structure and energy of 90° domain walls in crystalline iron having a (100) surface and ranging in thickness from 30 to 200 nm have been investigated numerically by minimization of the total wall energy using a slightly modified LaBonte method similar to that described by Aharoni and Jakubovics. For films of thickness in the range of 30–110 nm, both symmetric and asymmetric stable Néel wall structures were obtained. Below 45 nm, the former has the lower energy. Above 110 nm, only the asymmetric structure could be obtained. In addition to the wall energies, we provide measures of the wall width and data on the stray field external to the film for comparison with magnetic force microscopy studies.