Magnetoelectric and magnetodielectric properties of LSMO- (BCT-BZT) composites

The present paper reports magnetoelectric and magnetodielectric properties of La_0.67Sr_0.33MnO₃ and (Ba_0.7Ca_0.3TiO₃)- (BaZr_0.2Ti_0.8O₃) composites. y (La_0.67Sr_0.33MnO₃) + (1 - y) (x (Ba_0.7Ca_0.3TiO₃)- (1 - x) (BaZr_0.2Ti_0.8O₃)) particulate composites are prepared for x = 0.40, 0.45, and 0.50 and for y = 0.1 and 0.175. Ferroelectric compositions (x (Ba_0.7Ca_0.3TiO₃)- (1 - x) (BaZr_0.2Ti_0.8O₃)) are synthesized via ceramic route, while La_0.67Sr_0.33MnO₃ is synthesized via hydroxide co-precipitation route. Composites of La_0.67Sr_0.33MnO₃ and (Ba_0.7Ca_0.3TiO₃)- (BaZr_0.2Ti_0.8O₃) are synthesized using ceramic method. The crystal structures of La_0.67Sr_0.33MnO₃, (x(Ba_0.7Ca_0.3TiO₃)- (1 - x) (BaZr_0.2Ti_0.8O₃)), and composites are investigated using X-ray diffractograms, while microstructures are investigated using scanning electron microscope. The dielectric properties of (x (Ba_0.7Ca_0.3TiO₃)- (1 - x) (BaZr_0.2Ti_0.8O₃)) are determined as a function of temperature between 30 and 150 °C and at frequencies 1, 10, 100 kHz, and 1 MHz. The investigations on P-E hysteresis loops of (x (Ba_0.7Ca_0.3TiO₃)- (1 - x) (BaZr_0.2Ti_0.8O₃)) show useful values of maximum polarization (P_max) and remanent polarization (P_r). Dielectric study on composites is carried out as a function of frequencies between 1 kHz and 1 MHz and for magnetic field between 0 and 6 KOe. The linear magnetoelectric coefficient 'α' and quadratic magnetoelectric coefficient 'β' are measured with the help of custom-designed setup. The results on magnetoelectric and magnetodielectric properties of composites are interesting. (author)