Magnetic domain reversal behavior for various patterned hole depths

We have measured the domain reversal behavior for amorphous alloys of a rare earth-transition metal DyFeCo thin film with hole arrays by means of a modified Kerr microscope. We found that the shallow hole arrays had sharper domain boundaries than the deeper hole arrays when an applied magnetic field nears the coercivity. We also found that, when the hole depth is shallower, the magnetic anisotropy becomes more profound for the domain pinning effect. Moreover, the magnetic domain pinning effect due to the hole barrier becomes significantly practical as the hole depth approaches the film thickness.