Domain wall propagation in Fe-rich microwires

Abstract

We studied the velocity of domain wall propagation, v, of Fe 69Si 10B 15C 6 with different metallic nucleus diameter, d, and different total diameter, D ( d=14 μm, D=33 μm and d=18 μm, D=23.4 μm, respectively) in the temperature range between 78 and 300 K and at different frequencies of applied magnetic field. It is worth mentioning that v( H) dependence is essentially not linear, showing significantly higher domain wall mobility, S=d v/d H, at lower field limit. Domain wall mobility, S, increases significantly with increase in temperature. From v( H) dependence, the critical field, H cr, associated with the change of the slope on v( H) dependence and critical propagation fields H 01 and H 02 for the lower and higher field regions, respectively, are determined. All characteristics, v( H) dependence, S( H) dependence and H cr are sensitive to the sample geometry, i.e., to the internal stresses. The origin of such dependence on internal stresses is discussed in terms of magnetoelastic energy contribution.