A series of 30-nm-thick epitaxial NixCo1-x (002) alloy films are fabricated by DC magnetron sputtering. MgO (002) and SrTiO3 (002) single substrates are used for x 〉 0.5 and x 〈 0.5, respectively. The magnetocrystalline anisotropy of NixCO1-x (002) alloy films is studied in the entire composition region for 0 ≤ x ≤ 1.0. When x decreases, the cubic magnetic anisotropy constant K1 changes sign from negative to positive atx = 0.96 and becomes negative again atx = 0.79. It becomes more negative as x decreases from 0.79 to 0. The uniaxial anisotropy Ku is smaller than the K1 by a factor of two orders.
Interfacial magnetic anisotropy in a Pt/CO1-xFex/Pt multilayer is tuned by doping iron atoms into the cobalt layer. The perpendicular magnetic anisotropy and out-of-plane coercivity are found to decrease with increasing x. For a specific x, the out-of-plane coercivity acquires a maximal value as a function of the thickness of the CoFe layer. At low temperature, the coercivity is enhanced. Small coercivity but reasonably large perpendicular magnetic anisotropy can be obtained by controlling the x and CoFe layer thickness.
Tbx(Ni0.8Fe0.2)1-x films with x ≤ 0.14 are fabricated and the anomalous Hall effect is studied. The intrinsic anomalous Hall conductivity and the extrinsic one from the impurity and phonon induced scattering both increase with increasing x. The enhancement of the intrinsic anomalous Hall conductivity is ascribed to both the weak spin–orbit coupling enhancement and the Fermi level shift. The enhancement of the extrinsic term comes from the changes of both Fermi level and impurity distribution. In contrast, the in-plane and the out-of-plane uniaxial anisotropies in the Tb Ni Fe films change little with x. The enhancement of the Hall angle by Tb doping is helpful for practical applications of the Hall devices.