Room temperature frequency-dependent complex impedance and conductivity behavior of BaTiO₃–La_0.7Ca_0.3MnO₃ composites

Abstract

A series of composite materials (100 − x)BaTiO 3 (BTO) − (x)La 0.7 Ca 0.3 MnO 3 (LCMO) has been prepared using the solid state reaction route varying x in wt%. The influence of LCMO on the frequency-dependent complex impedance and conductivity of BTO has been investigated. The Cole–Cole plots of real and imaginary parts of the complex impedance indicates separate contributions of various factors, such as bulk effect, grain boundary, and interface effects in frequency-dependent conductivity in the composites. Non-Debye-like relaxation has been observed in the BTO–LCMO composites. Interestingly a typical universal dielectric response in the frequency-dependent conductivity at room temperature (300 K) has been found for all the compounds.