MFM observations of domain wall creep and pinning effects in amorphous Co_<i>x</i>Si_1−<i>x</i>films with diluted arrays of antidots

Abstract

Magnetic force microscopy (MFM) has been used to analyse the behaviour of domain walls in uniaxial amorphous CoxSi1−x films patterned with diluted arrays of antidots by electron beam lithography. The walls are found to be pinned by the antidot array when the antidot density is high enough along the easy axis. The expansion of reversed nuclei under the influence of the tip stray field has been observed in several consecutive MFM images of the same area, showing how the competition between line tension effects and pinning by the patterned holes governs the creep motion of the 180° walls across the array of antidots.