Influence of compositional variation on structural, electrical and magnetic characteristics of (Ba1−xGd) (Ti1−xFex) O3(0.2 ≤x≤ 0.5)

The effect of composition variation of (Ba 1− x Gd x )(Ti 1− x Fe x )O 3 (0.2 ≤ x ≤ 0.5) on structural, optical, electrical and multiferroic properties was investigated. The polycrystalline samples were fabricated by a chemico-thermal route. While the compound with composition x ≤ 0.3 has a tetragonal structure akin to BaTiO 3 , the higher compositions ( x > 0.3) crystallize in a mixed phase of the tetragonal and orthorhombic structure. The different polarization mechanisms in the compound were analyzed on the basis of ferroelectric–paraelectric phase transition at 120 °C, magnetic reorientation mediated by Gd 3+ ↔ Fe 3+ exchange interaction at 200 °C and that induced by antiferromagnetic ordering mediated through the Fe 3+ ↔ Fe 3+ exchange interactions at 380 °C. Analysis of ac conductivity on the basis of Jonscher's power law indicates the presence of correlated barrier hopping conduction mechanism in the samples. Among the studied samples, the composition with x = 0.3 exhibiting improved material properties like lower optical band gap and higher optical absorption, high dielectric constant (830 at room temperature and peak value of 3944 at 160 °C and 6478 at 377.5 °C), and the room temperature ME coefficient of 1.53 mV cm −1 Oe −1 have promising technological applications.