Magneto-Optical Study of the Surface Reversal Process in Amorphous Glass-Coated Microwires With Positive Magnetostriction

Abstract

Amorphous glass-coated microwires are well known by high domain wall velocities that reach up to 15 km/s. Previous works have shown that such fast domain wall dynamics can be manipulated by properly selected conditions of thermal annealing. Along with the magnetic anisotropy, the domain wall velocity is strongly influenced by surface shell of domains too. Here, the magneto-optical study of the surface reversal process in microwire is carried out by magneto-optical Kerr effect (MOKE) microscopy. It is shown that the nonplanar surface of the cylindrical samples gives rise to a complex MOKE. Trapping the domain wall in a potential, well confirmed the inclined structure of the domain wall. Such inclination can be found partially responsible for apparent high domain wall velocities measured by Sixtus-Tonks method in microwires.