The yttrium iron garnet（YIG） samples are prepared at different temperatures from 900℃ to 1300℃ by the metalorganic decomposition（MOD） method. The chemical composition and crystal structure of the samples are studied by scanning electron microscope（SEM）, XRD, and Mossbauer spectrometer. It is shown that the ratio of ferric ions on two types of sites, the octahedral and the tetrahedral, is increased with the sintering temperature. At 1300℃, the pure garnet phase has been obtained, in which the ferric ions ratio is 2：3 leading to the minimum magnetic coercivity and maximum saturation magnetization. These results provide a route to synthesize pure YIG materials as the basic materials used in various spintronics applications.
In this paper,the ^(90)Sr/^(90)Y coating effects on scattering width(SW) of cylindrical conductor targets are investigated.The electron density distribution of plasma around cylindrical targets of different radiuses is simulated under different radioactivities in normal or oblique incidence.In normal incidence,the SWs are examined as functions of frequency and scattering angle;while in oblique incidence,the SW is inspected as a function of incident angle at the frequency of 1.5 GHz.The results obtained are compared with those from an ideal perfect electric conductor(PEC) cylinder.It is demonstrated that the SW decreases over a wide frequency range in the back scattering region by coating a ^(90)Sr/^(90)Y layer on the cylindrical target.Moreover,the reduction in bi-static SW amplitude can reach 3-20 dB,when the incident angle is smaller than 30° at 1.5 GHz.It is a significant improvement in the stealth effect.
