Synergistic optimization of microwave characteristics in Yb-Sn-Cu Co-doped yttrium iron garnet: Tailoring magnetic and dielectric properties

Abstract

With the rapid advancement of modern telecommunication technology, a surging requirement for high-performance microwave materials emerges. Yttrium iron garnet (YIG, Y₃Fe₅O₁₂) is the basic material of microwave devices, and its property optimization has become a focal research direction in materials science. In this study, YIG samples co-doped with Yb, Sn and Cu were prepared by solid phase reaction method, and the chemical formula is Y_3-xYb_xFe_4.8Cu_0.1Sn_0.1O₁₂(x = 0.05, 0.10, 0.15, 0.20). Besides, the impact of doping on YIG microstructure and performance was studied through various testing methods. The results demonstrated that Yb³⁺, Sn⁴⁺, and Cu²⁺ were successfully doped into the YIG lattice. Specifically, Cu²⁺-Sn⁴⁺ replaced the Fe³⁺ ions at the octahedral sites, and Yb³⁺ entered the dodecahedron and replaced the Y³⁺ ions at the dodecahedral sites, altering the lattice parameters and microstructure of YIG. Regarding the magnetic characteristics, as the content of Yb increased, saturation magnetization, ferromagnetic resonance (FMR) linewidth, and permeability initially decreased and subsequently increased. When the doping concentration was x = 0.15, the FMR linewidth attained its minimum value of 39 Oe, and the saturation magnetization also reached a minimum of 25.3 emu/g. In terms of dielectric properties, the dielectric constant initially declined and then rose as the value of doping concentration increased, reaching a minimum value of 17.01 at x = 0.15. The dielectric loss reached its minimum with the doping concentration being x = 0.15. Overall, this study provides a practical method for preparing high-performance YIG for microwave devices.