Interdependence between electrical and magnetic properties of polycrystalline cobalt-substituted tungsten bronze multiferroic ceramics

Abstract

Polycrystalline cobalt-substituted tungsten bronze ferroelectric ceramics with chemical composition Ba 5 CaTi 2Àx Co X Nb 8 O 30 (x ¼ 0:00, 0.02, 0.04 and 0.08) were synthesized by solid state reaction technique. X-ray diffraction (XRD) technique was used to confirm the phase formation and it revealed the formation of single phase tetragonal structure with space group P4bm. The surface morphology of the samples was studied by using the scanning electron microscopy (SEM) technique. The dielectric properties such as dielectric constant and dielectric loss have been investigated as a function of temperature and frequency. The P-E and M-H studies confirmed the coexistent of ferroelectricity and magnetism at room temperature. The P-E loop study indicated an increase in the coercive field while the M-H study depicted a decrease in the magnetization with the incorporation of cobalt ions.