AIP Advances (Sep 2012)
Effect of electrode resistance on dielectric and transport properties of multiferroic superlattice: A Impedance spectroscopy study
Abstract
Fundamental microscopic processes that take place throughout of ferroelectric PbZr1−xTixO3 (x = 0.48) (PZT) and ferromagnetic La1−xSrxMnO3 (x = 0.33) (LSMO) superlattices (SLs) architecture including the influences of electrode on functional properties are analyzed using impedance spectroscopy technique (IS). Temperature and frequency dependence impedance and ac conductivity are investigated in the ranges of 100–600 K and 102–106 Hz suggesting a strong dependence between temperature and electrode contribution in the electrical properties. The results are interpreted using the alternative Z′ as a function of Z″/F representation, more commonly this representation applied in the cases when the complex impedance curves show overlapped arcs due to the relative small differences in relaxations frequencies. Activation energy is obtained from the Arrhenius plot of relaxation time and ac conductivity in order to identify the conduction mechanism present in the superlattices.