Transition-metal-induced magnetism in particles of CaYAl3O7: Ni, Fe and Co

Abstract

Here, we report the first observation of transition-metal-induced magnetism in CaYAl₃O₇ particles doped with Ni, Fe, and Co ions synthesized by the Pechini method. Structural characterization by X-ray diffraction followed by Rietveld refinement confirmed preservation of the tetragonal melilite phase without detectable secondary phases. Microstructural parameters such as crystallite size, lattice strain, and dislocation density were evaluated, revealing only minor structural distortions after doping. Raman spectroscopy further confirmed the structural integrity of the host lattice while indicating local symmetry perturbations caused by dopant incorporation. Magnetic measurements performed by vibrating sample magnetometry revealed clear hysteresis loops with finite coercivity and remanent magnetization, following the trend Co < Fe < Ni. The observed magnetic behavior is attributed to exchange interactions among localized magnetic moments introduced by the transition-metal ions. These results demonstrate that doped CaYAl₃O₇ is a promising multifunctional material combining optical and magnetic functionalities for applications in sensing, photonics, and magneto-optic devices.