MAGNETIC DOMAIN-STRUCTURES IN ULTRATHIN CO AU(111) - ON THE INFLUENCEOF FILM MORPHOLOGY/

The magnetic domain structures in thin hcp Co films grown on Au(111) h ave been investigated by means of scanning electron microscopy with po larization analysis. The domain pattern in films with out-of-plane mag netization were analyzed in the as-grown state and after annealing. Th e heat treatment causes the morphology and the magnetic microstructure to change drastically. The films become smoother and the domain patte rn exhibits a characteristic thickness dependence. A collapse of the d omain size near the reorientation transition is found, consistent with micromagnetic theory.