COERCIVE PINNING OF MAGNETIC DOMAIN-WALLS IN PARTLY CRYSTALLIZED AMORPHOUS-ALLOYS

We analyze coercive pinning of domain walls (DW) on three samples of amorphous alloys Fe64Co21B15 and Fe68Co17B15 with strong induced magnetic anisotropy. Magnetic domains are in the form of parallel stripes and so we can extract the DW pinning from other magnetization processes. The annealing caused in one sample partial crystallization and there are still traces of crystallinity in the second sample. The last sample appears to be completely amorphous. We found that the degree of partial crystallinity of the alloy has very large effect on coercive pinning of moving DW: While in purely amorphous alloy the coercivity is less than 0.02 mT, it increases to 0.095 mT and 0.42 mT with increasing crystallinity. Our results demonstrate that the rotation process is much more favorable from the point of view of hysteresis losses.