Determination of the domain wall energy and the exchange constant from magnetic susceptibility measurements in Ni-5 wt% Mn alloy

Abstract

The magnetic susceptibility ( χ) and the magnetic anisotropy ( K) are used to study the effect of grain boundaries on the behaviour of domain wall displacements in Ni-5 wt% Mn alloy. The observed dependence of the maximum magnetic susceptibility ( χ max) was used to calculate the magnetic domain wall surface energy and the boundary pinning force, and leads to the confirmation of the domain wall size theory in ferromagnetic material. From the simple measurements of χ max and K, the domain wall thickness (δ) and the exchange constant ( A) were calculated.