Complementary imaging of granular Co-Ag films with magneto-optical indicator film technique and magnetic force microscopy

Abstract

A magneto-optical indicator film (MOIF) technique and magnetic force microscopy were used for visualization and direct real-time experimental study of the magnetization processes of magnetic Co90Ag10 granular films. It is shown that the magnetization reversal of the as-deposited films follows a specific two-step course. The first stage is characterized by gradual spin rotation to large angles up to 90° without domain formation. Further magnetization reversal proceeds by the nucleation and motion of zigzag-shaped domain walls. The dendritic structure of the domain walls was observed using both techniques. Also tracks of magnetic inhomogeneities remaining behind moving zigzag-shaped domain walls was revealed by MOIF.