Structural, magnetic and transport properties of magnetoelectric composites

• Published in: Journal of magnetism and magnetic materials Vol. 345; pp. 89 - 95
• Main Authors: Rahman, M. Azizar, Gafur, M.A., Hossain, A.K.M. Akther
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier 01.11.2013
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Dielectric constant; Dielectric loss; Dielectric loss and relaxation; Dielectric properties of solids and liquids; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Dispersions; Electric fields; Electrical conductivity; Exact sciences and technology; Ferrite; Magnetic properties and materials; Magnetomechanical and magnetoelectric effects, magnetostriction; Permeability; Permittivity (dielectric function); Physics; Sintering; Dielectric dispersion; Electrical conductivity; Volume fraction; Composite; Magnetic field effects; X-ray diffraction; XRD; Fabrication property relation; Magnetoelectric voltage coefficient; Ferrites; Composite materials; Barium zirconates titanates; Magnetic and transport property; Magnetoelectric effects; Sintering; Chemical composition; Transport processes; Permittivity
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2013.06.004

Magnetoelectric composites of nominal chemical compositions (y)Mn0.45Ni0.05Zn0.50Fe2O4+(1-y)BaZr0.52Ti0.48O3 (where y varies from 0 to 1.0 in steps of 0.20) were prepared by the standard solid state reaction technique. The samples were sintered at various temperatures. X-ray diffraction patterns confirm the presence of the constituent phases. The initial permeability increases with increasing ferrite content and also with increasing sintering temperature. However, there is a slight decrease in initial permeability value for samples sintered above 1573 K. The dielectric dispersion is observed at lower frequencies (<103 Hz) due to interfacial polarization. The dielectric constant is almost independent at high frequencies (>104 Hz) for a particular composition because of the inability of electric dipoles to follow the fast variation of the alternating applied electric field. The ac electrical conductivity increases with increasing frequency, suggesting that the conduction is due to small polaron hopping. The increase in dielectric constant and dielectric loss corresponds to the increase in ac electric conductivity with increasing sintering temperature up to 1573 K. The magnetoelectric voltage coefficient of the composites decreases with increasing ferrite content and dc magnetic field.