Variations of the local anisotropy versus Tb content in amorphous CoZrTb thin films

Abstract

The magnetic properties of rf sputtered amorphous (Co93Zr7)100−xTbx thin films were investigated as a function of Tb content for 0≤x≤2 by transverse biased initial susceptibility measurements. The deposition was performed in a magnetic field. This films exhibit a very well-defined in-plane anisotropy with negligible long-range fluctuations and a small coercive field Hc, in accordance with the experimental data. The overall variations of the transverse susceptibility are related to the ripple, and the variations of the structure factor S with composition was measured. The local anisotropy Kloc, deduced from S, increases with the increasing amount of Tb in the layers. The results are discussed in terms of the single-ion anisotropy of the rare earth.

FeCoHfN thin films fabricated by co-sputtering with high resonance frequency

“…4(a). The effective damping coefficient˛e ff is derived from curve-fitting and the frequency linewidth f is determined from the following formula [20]: The above equation explains well the similar behaviors of the frequency linewidth f and the effective damping coefficient˛e ff as in Fig. 5(a).…”

“…According to Hoffmann, there is an additional effective isotropic field that contributes to the anisotropy field obtained from permeability spectra in addition to the static intrinsic anisotropy field. This additional effective field dependent on a so-called ripple constant may originate from the local random anisotropies which are in isotropic distribution [18][19][20][21] and as a result it is not included in H sta K from the static measurement as that from the dynamic measurement [19,20]. The difference between H sta K and H dyn K may be assigned as rotatable magnetic anisotropy field (so-called dynamically induced internal field or ripple field) [22].…”

Investigation of the microstructure, magnetic and microwave properties of electrodeposited NixFe1−x(x=0.2–0.76) films

“…According to this theory, there is an additional effective isotropic field that contributes to the anisotropy field obtained from permeability spectra beside the static intrinsic anisotropy field. This additional effective field depends on a ripple constant that originate from the local anisotropies which are in isotropic distribution [27,28] and consequently, it is not included in H sta K from the static measurement and hence contributes to the difference from the dynamic measurement [29].…”

Induced and local anisotropies in amorphous CoZr–rare earth thin films containing Pr, Nd, and Tb

“…In particular, amorphous CoZrRE thin films are promising candidates to be employed in magnetic heads as they exhibit good frequency response of the permeability, 2 high saturation magnetization, low coercivity, low magnetostriction, 3 good mechanical properties 4 and, if prepared in adequate conditions, a very well defined in-plane uniaxial anisotropy K u . 5,6 On the other hand, the films under study in the present article are very interesting to analyze the physical origin of in-plane uniaxial anisotropy (K u ) in thin films.…”