Large Barkhausen Discontinuities of Amorphous Ribbon with Domain Wall Pinning

Abstract

Non-magnetostrictive Fe-Co-Si-B amorphous ribbons annealed in a demagnetized state exhibits magnetization reversal with large Bazkhausen discontinuities due to domain wall pinning caused by the locally induced anisotropy. To increase the stability of the large Barkhausen discontinuities, domain walls, domain patterns and magnetization reversal process of wall pinned amorphous ribbons were studied in detail using a Kerr microscope.
It was found that the domain wall width and its pinning field were increased markedly by annealing and that the large Barkhausen discontinuities caused by depinning of one of walls of multiple closure domains existing near the ribbon ends due to demagnetizing field. It was also found that the instability of the large Barkhausen discontinuities is related to the dispersion of depinning field of walls of multiple closure domains.