Application of the analytic representation of bloch walls in thin ferromagnetic films to calculations of changes of wall structure with increasing anisotropy

Abstract

The structure of 180° domain walls in thin ferromagnetic films with different values of uniaxial anisotropy constant, K, is investigated theoretically, using analytic functions to represent the magnetization distribution. In films with exchange constant 10⁻⁶erg cm⁻¹, thickness 1000 A, and saturation magnetization 800 G, domain walls are found to have a two-dimensional structure which is almost free from stray fields, when K is less than about 10⁵ erg cm⁻³. For K between about 10⁵ and 10⁶erg cm⁻³, the structure is still two-dimensional, but contains increasing amounts of stray fields. The structure switches to being one-dimensional at K slightly above 10⁶ erg cm⁻³. It is suggested that it may be possible to observe the transition between the two types of structure by studying cobalt films at different temperatures.