Effect of Electrical Properties on Gd modified BiFeO3-PbZrO3
  The 0.5(BiGdxFe1-xO3)-0.5(PbZrO3) composite was synthesized using a high temperature solid-state reaction technique. Preliminary X-ray structural analysis confirms the formation of the composite. The dielectric constant and loss tangent have been studied. The hysteresis loop suggest that the material is lossy. The impedance parameters were studied using an impedance analyzer in a wide range of frequency (102-106 Hz) at different temperatures for all samples. The Nyquist plot suggests the contribution of bulk effect as well as grain boundary effect and the bulk resistance deceases with rise in temperature for all samples. The electrical transport confirms the presence of hopping mechanism in the material. The dc conductivity increases with rise in temperature. The frequency variation of ac conductivity shows that the compound obeys Jonschers universal power law and confirms the Small Polaron (SP) tunneling effect due to low activation energy for all samples. Temperature dependence of dc and ac conductivity indicates that electrical conduction in the materials are thermally activated process. 
S. K. Satpathy, N. K. Mohanty, A. K Behera, K. C. Patra, B. Behera and   P. Nayak
cond-mat.mtrl-sci