非晶質Al_20_3膜上均一分散α-Feナノ粒子の構造と磁性  [in Japanese] Structure and Magnetic Properties of Homogeneously Dispersed α-Fe Nanocrystals on a-Al_2O_3  [in Japanese]

Granular magnetic films composed of randomly oriented α-Fe nanoparticles on amorphous Al_2O_3 were synthesized by electron beam deposition. The nanocrystals were propared by taking advantage of the growth of α-Fe on fcc-Au "seed" nanoparticles. For films with an average Fe thickness of less than 1 nm, the resistivity was quite large (10^4-10^7μΩcm). With these films, the temperature dependence of the resistivity ρ can be fitted by ρ=Aexp(αT^<-1/2>), where A and α are material constants. The films showed a magnetoresistance of about 1.4% in an applied field of 10 kOe at room temperature.