High dielectric constant and magnetic properties of Bi-In Co-substituted YIG ferrites

In this paper, the Bi-In co-substituted YIG ferrite materials composed of Y3_xBixFe4.55In0.45O12 (x = 0.0-1.0 with a step of 0.2) were synthesized by a conventional solid-state route. Samples with different Bi3+ ion contents were sintered at different temperatures. The phase formation, microstructure, dielectric and magnetic properties of samples were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), impedance analyzer, vibrating sample magnetometer (VSM), and ferromagnetic resonance (FMR). The results showed that Bi3+ ion substitution could reduce the sintering temperature, increase the bulk density (db), improve the dielectric con-stant (epsilon' = 22.26@100 MHz at x = 1.0) and keep a high saturation magnetization (4 pi MS = 1700-1850 Gs), but led to the increase of the FMR linewidth (Delta H = 316.21 Oe at x = 1.0).