Quantifying magnetic anisotropy dispersion : theoretical and experimental study of the magnetic properties of anisotropic FeCuNbSiB ferromagnetic films

Abstract

We performed a theoretical and experimental investigation of the quasi-static magnetic properties of anisotropic systems. We considered a modified Stoner-Wohlfarth model to describe anisotropic systems, and a distribution function to express the magnetic anisotropy dispersion. We also proposed a procedure to calculate the magnetic properties from experimental results of the quadrature of magnetization curves, thus quantifying the magnetic anisotropy dispersion. To test the robustness of the approach, we applied the theoretical model to describe the quasi-static magnetic properties of amorphous FeCuNbSiB ferromagnetic films, and directly compared the theoretical results with longitudinal and transverse magnetization curves measured for the films. Our films are characterized by anisotropy fields between 7 and 10.5 Oe, values compatible with that obtained for several amorphous magnetic materials, as well as by anisotropy dispersions expressed by exponents n between 14 and 30. Thus, the excellent agreement between numerical calculation and experimental results provides support to confirm the validity of our theoretical approach to describe the magnetic properties of anisotropic amorphous ferromagnetic films.