Temperature, frequency and bias voltage effects on the electrical transport properties of (Sm-Pr-Sr)MnO3 perovskite

Abstract

In the present work, we report on the investigations of the electrical transport properties for Sm0.45Pr0.1Sr0.45MnO3. Beyond the metal-semiconductor transition, the Shklovskii-Efros, Shimakawa, and hopping models are used to explain the transport over the nearest sites models. The applied bias voltage suggests the enhancement of the electrical conductivity, but it does not affect the metal-semiconductor transition. In the AC regime and at low temperatures, the conductivity can be explained by the hopping motion of charge carriers between correlated barriers. Complex impedance investigation confirms that the sample has a negative temperature coefficient of resistance. The combination investigation of the complex impedance and the electrical modulus confirms the roles of both grain and grain boundary effects and indicates that the studied ceramic has a non-Debye relaxation type.