Microwave Properties of Polycrystalline Rare Earth Garnets

Abstract

A number of garnets including yttrium garnet, Y₃Fe₅O₁₂, and mixed garnets of the forms (Y_1−αSm_α)₃Fe₅O₁₂ and (Y_1−βGd_β)₃Fe₅O₁₂ have been prepared. X‐band ferromagnetic resonance and saturation magnetization have been measured as a function of temperature. At room temperature samarium substitution for yttrium produces an approximately linear increase of line width with samarium content with practically no change in magnetization. Gadolinium substitution, on the other hand, has a much smaller effect on line width but produces an approximately linear decrease in saturation magnetization. Possible microwave application of these materials are discussed.