摘要
[Fe <sub>62</sub> Co <sub>19</sub> Ga <sub>19</sub> (x)/Py(40-x)] <sub>5</sub> /glass multilayered films, where x=0, 5, 10, 15, 20 nm, y=x(nm)/40(nm), and 0≤y≤1, were made by the magnetron sputtering method at room temperature. The total number of combined [Fe-Co-Ga/Py] unit-layers was five. The total film thickness (t <sub>f</sub> ) was fixed at 200 nm. We have performed two kinds of experiments on these films: (i) the saturation magnetostriction (λ <sub>S</sub> ) measurement, and (ii) the complex permeability (μ=μ <sub>R</sub> -jμ <sub>I</sub> ) experiment to find the resonance frequency (f <sub>R</sub> ) as a function of external magnetic field (H <sub>E</sub> ). By definition, the microwave power absorption P <sub>abs</sub> at ferromagnetic resonance (FMR) for a metallic conductor is written as (Formula presented.). We define the half-width of the absorption peak Δf as Δf ≡ Δf <sub>S</sub> +Δf <sub>A</sub> , where Δf <sub>S</sub> and Δf <sub>A</sub> are the symmetric and asymmetric parts in Δf. The degree of asymmetry, Δf <sub>A</sub> /Δf, of each absorption peak is associated with the structural and/or magnetic inhomogeneity in the film. The main findings from this study are summarized as follows: (A) maximum λ <sub>S</sub> occurs in the y=1 film, and as y increases, λ <sub>S</sub> increases; (B) biasing field for magnetostriction decreases greatly by adding Py layers; (C) the magnetostriction sensitivity remains almost constant in the range 0.4<y 蠆 1; (D) μ <sub>R</sub> increases, as y decreases. Thus, from this study we conclude that among all the [Fe <sub>62</sub> Co <sub>19</sub> Ga <sub>19</sub> /Py] <sub>5</sub> /glass films, the [Fe <sub>62</sub> Co <sub>19</sub> Ga <sub>19</sub> (30)/Py(10)] <sub>5</sub> /glass film should be the most suitable for applications in nano-magnetic switching devices.