Dielectric, Optical, and Magnetic Behaviors of Magnesium Iron-Based Double Perovskite

Abstract

The multiferroic nature of the Mg2FeNbO6 complex oxide ceramic, prepared by a mixed oxide reaction route is presented. A phase transformation to the tetragonal symmetry was identified from refinement analysis. The optical band gap was estimated to be 1.58 eV with the direct allowed transition consideration. From the temperature-dependent dielectric parameter study, magnetic phase transitions at various Tc values were seen, together with some glassy dynamics. The CIS spectroscopy revealed the dominance of grains toward the complex impedance response of the composite. The conductivity of the compound was found to be following Jonscher’s universal power quite ideally. The plot of μB/unit mass versus manifests itself as a weak but well-saturated magnetic ordering in the ceramic, with a low retentivity value of 0.0286 emu/gm. The multiferroic nature of the oxide material is confirmed by the existence of a room temperature (P-E) hysteresis loop, with remnant polarization of Pr=1.2 µC/Cm2.