Structural, Dielectric, Complex Impedance and Magnetoelectric Properties of the (1-x) KNbO3 - xMgFe2O4 Composites

Abstract

Ferrite-ferroelectric nanoparticle composites have a promising potential for a wider range of applications for the manufacturing of new-generation devices due to the tenability of their electric and magnetic orders. In this present work, room-temperature magnetoelectric (ME) coupling studies of KNbO3/MgFe2O4 composites having a general formula (1-x) KNbO3 - xMgFe2O4 (where x = 0, 0.1, 0.3, 0.5, 0.7, 0.9, 1) is presented.  The presence of the cubic spinel-ferrite phase of MgFe2O4 and the orthorhombic ferroelectric phase of KNbO3 were confirmed by the structural analysis which was employed using X-ray diffraction (XRD), Raman spectroscopy, and morphology and grain size using Transmission electron microscopy (TEM). Magnetization versus magnetic field (M-H) measurements conform to ferromagnetic ordering and show improved magnetization with the increase in the ferrite phase. The existence of coupling between ferroelectric and ferromagnetic ordering was performed using a lock-in amplifier ME measurement setup. All the composite samples show good linear magnetoelectric coupling that increases with increasing ferrite content.  This composite nanostructure with a well-defined interface provides the possibility of an ideal model of room temperature ME coupling which is significant from the technological point of view for a variety of miniaturized next-generation device applications.