Journal de la science des matériaux et des nanomatériaux

Abstrait

Properties Elucidations of Mn-doped Ba_0.7Sr_0.3Ti_1-xMn_xO₃ Ceramics

Jamal Uddin Ahamed, Robayet Ahasan, Fairoz Abida, MNI Khan

Ba_0.7Sr_0.3Ti_1-xMn_xO₃ ceramic with fixed doping of Sr at Ba site and Mn doping with various concentrations at the Ti site has been carefully prepared with conventional solid state reaction technique. As the behavior of materials with the variation of frequency, electric field, and temperature is a focus of interest for technological advantage in the field of microelectronics, telecommunication and spintronics, we have evaluated different characteristics of the synthesized samples. X-ray diffraction and Scanning Electron Microscopy (SEM) were employed to measure structural and morphological properties of the prepared samples. XRD analysis confirm the tetragonality of the crystal and the volume of the unit cell is observed slightly different except for x=0.3, with the increase of Mn content. SEM images confirm increasing grain size with Mn doping. Dielectric constant and AC conductivity assessed the dielectric properties of Ba_0.7Sr_0.3Ti_1-xMn_xO₃ in a wide frequency range from kHz to GHz region. This result reveals that with the concentration of Mn the dielectric constant also increases, most importantly for 30% Mn substance with Ti. The results also showed that there is a high dielectric constant at the KHz region for the sample which decreases with the upward frequency. Magnetic permeability was observed to increase with 10% and 30% Mn substitution. VSM data indicated that samples exhibit ferromagnetic properties with feeble coercive field and with the increase of Mn ion concentration ferromagnetic order also found to increase. The multiferroic materials that we have developed can be used in spintronic devices like memory devices, spin transistors, spin diodes, sensors.