Dynamics of charge carriers in doped manganite based on conductivity measurements and theoretical models

Transport properties of La0.5Ca0.1Ag0.4MnO3 have been studied. The dynamics of the charge carriers are studied based on scaling approaches. La0.5Ca0.1Ag0.4MnO3 ceramic reveals various conduction mechanisms. The compound exhibits a semiconductor behavior. The conductivity appears temperature independent beyond Tsat = 560 K. At low temperatures, the transport of charges is governed by the activation of the VRH mechanism. Greaves-VRH is the best model that describes the transport properties in the intermediate temperature interval. Beyond θD/2 temperature, the conductivity is thermally activated confirming the validity of Mott theories. Jonscher law explains the transport properties below 320 K. The dynamic regions are investigated in term of an activated CBH process and a nearly constant loss. Beyond T = 340 K, the conductivity is fitted using the Drude model. Also, the validity of the TTSP principle is confirmed using scaling approaches. Corrected Summerfield scaling confirms the presence of inter-ionic Coulomb interactions.