Correlation between magnetic and electric properties based on the critical behavior of resistivity and percolation model of La0.8Ba0.1Ca0.1MnO3 polycrystalline

We investigated the magneto-electrical properties of a La0.8Ba0.1Ca0.1MnO3 polycrystalline sample, prepared by the polymerization-complex sol-gel method. Comparison of experimental data with the theoretical models showed that in the metal-ferromagnetic region, the electrical behavior of the sample is quite well described by a theory based on electron-electron, electron-phonon and electron-magnon scattering and Kondo-like spin dependent scattering. For the high temperature paramagnetic insulating regime, the adiabatic small polaron hopping model was found to fit well with the experimental curves. The estimated critical exponents, obtained from resistivity, were (beta = 0.516 +/- 0.013, gamma = 1.181 +/- 0.005 and alpha = 0.004). They were very close to those predicted by the mean-field model. These results were in good agreement with the analysis of the critical exponents from magnetization measurements.