title: Origin of magnetocapacitance in chemically homogeneous and inhomogeneous ferrites.
abstract: The present work mainly focuses on the magnetodielectric (MD) effect in polycrystalline Ni0.9-yCuyZn0.1Fe1.98O3.97 (y = 0, 0.1, 0.2, 0.3, 0.4, 0.5) ferrite synthesized by a solid-state reaction method. Sintered samples showed the formation of CuO-rich grain boundary segregation for y≥ 0.2. The appearance of segregation made the present material chemically inhomogeneous and electrically heterogeneous. A negative MD response was observed in homogeneous ferrite for y = 0 and 0.1 due to lattice distortion (an intrinsic effect), whereas a positive MD response occurs in chemically inhomogeneous segregated ferrite (y≥ 0.2) due the collective effects of Maxwell-Wagner (MW) polarization with intrinsic magnetoresistance (an extrinsic effect).
authors.affiliation: Microwave Laboratory, Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India. rajimmondal.phys@gmail.com.
authors.forename: R A
authors.initials: RA
authors.lastname: Mondal
authors.forename: B S
authors.initials: BS
authors.lastname: Murty
authors.forename: V R K
authors.initials: VR
authors.lastname: Murthy