Crystal structure and magnetic properties of (Ni$_{1-x}$Zn$_{x}$)Fe$_{2}$O$_{4}$ composition graded ceramic

A homogeneous multilayered graded (Ni$_{1-x}$Zn$_{x}$)Fe$_{2}$O$_{4}$ ($x$ = 0–0.2) ferrite-based ceramic is prepared via thick-film technology using the two-stage sintering mode. The unit cell parameters and main magnetic characteristics, such as the Curie temperature, specific magnetization, and magnetic susceptibility are determined; the magnetic hysteresis loops are studied. The temperature and field dependences of specific magnetization and magnetic susceptibility are analyzed. The increasing zinc content in ceramic is shown to favor a rise in the specific magnetization from 45.30 to 70.95 A m$^{2}$ kg$^{-1}$ at room temperature and in the magnetic moment from 2.09 to 3.48 $\mu_{\mathrm B}$ near the liquid nitrogen temperature. The augmentation of the unit cell parameter $a$ by $\sim$0.8% causes the attenuation of magnetic interplay between the cations and a decrease in the Curie temperature from 790 to 720 K. The magnetization in multilayered structures is examined under the external magnetic field applied parallel and perpendicular to the layer plain. No magnetic hysteresis loop shift is found in the different geometries of the experiment, and the probable causes of its lack are analyzed in the bulk magnetic composition graded materials.