Domain nucleation and wall velocity in magneto-optical amorphous thin films

Abstract

Domain nucleation and growth kinetics were investigated in sputter-deposited amorphous thin films of Tb20.2Fe67.8Co12.0. After magnetically saturating the films, a reverse external field was applied and the specimens were pulse-heated by an excimer laser. During this heat treatment the reversal of the magnetization was observed in-situ using the magneto-optical Kerr effect. In addition the domain nucleation was studied using a polarizing microscope. Combining the nucleation and magnetization reversal measurements the domain wall velocity was determined as a function of temperature at three different applied external fields. The results are discussed with reference to existing models for domain wall motion.