Low dielectric loss and narrow FMR linewidth of Ca-Ge co-substituted YInIG ferrites for microwave device application

Abstract

Recently, the yttrium iron garnet (Y3Fe5O12, YIG) ferrite material is widely applied in the microwave devices due to its good frequency stability and loss magnetic loss. In this work, Y3−xCaxIn0.6GexFe4.4−xO12 (x = 0.0–0.6 with a step of 0.1) materials were synthesized by the conventional solid-state reaction method. The effects of Ca-Ge co-substitution on the microstructural, dielectric and magnetic properties of YInIG materials were investigated. Ca-Ge co-substitution did not change the phase formation of YInIG ferrite, and enhanced dielectric and magnetic properties of samples. The high saturation magnetization (4πMs), low dielectric constant (εr), low dielectric loss (tanδε), small coercivity (Hc) and narrow ferromagnetic resonance (FMR) linewidth (ΔH) were obtained for high frequency microwave device application. When substituted content x = 0.4, Y2.6Ca0.4In0.6Ge0.4Fe4O12 has the optimum microwave properties: εr = 13.884@10.8 GHz, tanδε = 3.053 × 10–4, Hc= 22.75 Oe, 4πMs = 1226.83 Gs, ΔH= 19.3 Oe. The narrow FMR linewidth and low loss dielectric loss of the investigated samples suggested the possible use of these materials in high frequency applications.