Effects of Ho doping on the structural, dielectric, and magnetic properties of GdMnO3 ceramics

The effects of Ho doping on the microstructure, composition, vacancy defects, and magnetic properties of Gd 1 − x Ho x MnO 3 (GHMO, x = 0.00-0.20) ceramics synthesized using the solid-state reaction method were investigated. The results revealed that the orthorhombic perovskite structure was maintained in all GHMO ceramics, while the addition of Ho ions induced lattice deformation. Ho doping displayed the function of decreasing the dielectric loss and improving the dielectric constant frequency stability. The positron annihilation lifetime spectroscopy demonstrated that when Ho content increased, the vacancy concentration initially increased and subsequently decreased. The magnetic properties measurements showed that Ho doping had a significant impact on the long-range order of Gd moments, magnetic transition temperature, and magnetization. The correlation study of structure and properties shows that the development of magnetic characteristics was strongly related to the vacancy concentration in GHMO samples.