Domain structure dynamics of amorphous Fe64Co21B15 and Co77B23 ribbons studied by three-dimensional neutron depolarization

Relaxation phenomena related to domain structure dynamics in amorphous ferr omagnetic Fe64Co21B15, and Co77B23 samples were studied by time-resolved th ree-dimensional neutron depolarization and a conventional magnetic inductio n technique. Different initial domain structures were induced either by app lying external stresses or by stress annealing. A theoretical model was dev eloped to describe the observed time dependence of neutron depolarization u pon passage through such samples. It is shown that the domain structure app roaches the equilibrium state with stable domain wall positions at a rate t hat depends essentially both on the sample composition and on the induced m agnetic anisotropy. (C) 1999 American Institute of Physics. [S0021-8979(99) 01402-4].