Substitution modification mechanism of YIG ferrite with a high spin-wave linewidth via fast relaxation Dy3+ ion doping and sintering modulation

YIG ferrites are often used as nonreciprocal materials in microwave ferrite devices because of their low microwave magnetic and dielectric losses. To comply with the trend of planarization and integration of microwave systems, YIG ferrites are required to withstand higher powers. In this study, we investigated the variation in material microwave properties with material composition and microstructure. The experimental results show that doping the material with high-relaxation ions Dy3+ combined with modulating the sintering holding time can effectively improve the material's high-power microwave signal withstanding capability, and YIG ferrite with a spin-wave line width of 18.7 Oe is obtained. In addition, when the average grain size of the material is controlled within 5 μm, the effect of the average grain size on the spin-wave linewidth is more noticeable than that of Dy3+ substitution.