Studies on charge transport in Al-doped La0.7Ca0.3Mn1−xAlxO3 manganites

In this communication, we report the results of the studies on the effect of non-magnetic Al3+-doping on structure and properties of La0.7Ca0.3Mn1−xAlxO3 (LCMAO) manganites synthesized by conventional solid state reaction (SSR) route. The Rietveld refinement of the X-ray diffraction (XRD) data confirms the single phasic nature of the samples without any detectable impurities. All the samples exhibit metal to insulator transition (TP) which decrease with increase in Al3+ doping concentration while it increases with applied magnetic field. To understand the nature of charge transport in metallic and insulating regions of resistivity, various models and mechanisms have been used to fit the observed experimental data.