Magnetoelectric coupling, dielectric and electrical properties of xLa0.7Sr0.3MnO3 - (1−x) Pb (Zr0.58Ti0.42)O3 (x = 0.05 and 0.1) multiferroic nanocomposites

We have investigated magnetoelectric coupling, dielectric and electrical properties of xLa0.7Sr0.3MnO3(LSMO)- (1-x) Pb(Zr0.58Ti0.42)O3 (x = 0.05 and 0.1) nanocomposites, prepared through low temperature pyrophoric reaction process. Magnetoelectric response has been detected in these multiferroic nanocomposites at room temperature attributing the presence of magnetostriction properties of piezomagnetic material. Noticeably, all nanocomposites are found to exhibit room temperature ferroelectric behavior. Studies of dielectric constant of those nanocomposites reveal the Maxwell Wagner interfacial polarization at low frequency regime. The ac electrical properties of nanocomposites have been studied employing impedance spectroscopy technique. The value of impedance has been found to decrease with increase in magnetic field attributing to the depinning of LSMO domain walls at the grain boundaries pinning centres and thereby enhancing the spin dependent transport mechanism in the composites. Impedance study at different temperatures shows temperature dependent electrical relaxation process in the system. The activation energy is estimated from Nyquist plots, dc and ac conductivity data using the Arrhenius relation. This is indicating that the same type of charge carrier is responsible for both the relaxation and the conduction processes in the system. Ac conductivity curves follow a Jonscher's double power law. The conduction mechanism in temperature is mainly due to the small and large polaronic hopping in the system.