Domain wall pinning, bulging, and displacement in circumferential domains in CoFeBSi amorphous wires

A detailed study of the complex inductance response of as-cast CoFeBSi wire s as a function of frequency (100 Hz-13 MHz range) and circular field ampli tude [0.1-17 A/m room mean square (rms) on the surface of the wire] in the giant magnetoimpedance arrangement is presented. The analysis of experiment al results show evidence of magnetization processes associated with circumf erential domain walls, such as domain wall pinning, bulging, and displaceme nt. The unpinning field was measured as 0.2 A/m (rms) at 5 kHz. It is shown that the analysis of spectroscopic plots of real and imaginary inductance leads to characterization of the magnetization process involved. (C) 2000 A merican Institute of Physics. [S0021-8979(00)20708-1].