The influence of Sm doping in the electron-doped manganites La0.9Te0.1MnO3

The effect of Sm-doping on structural, magnetic and transport properties in the electron-doped manganites La0.9−xSmxTe0.1MnO3 (0 ≤ x ≤ 0.15) with fixed carrier concentration is investigated. All samples show rhombohedral structure with the space group R3¯C. Both the Curie temperature TC and magnetization M of samples decrease with increasing Sm-doping level. For all samples, there exists two metal-insulator (M-I) transitions in the temperature dependence of the resistivity curves ρ(T). The resistivity of the sample increases with increasing Sm-doping level. By fitting theρ(T) data in the high paramagnetic (PM) region, it is found that the transport properties are dominated by the small polaron conduction (SPC) mechanism. With increasing Sm-doping level, the polaron binding energy increases, which is ascribed to the lattice distortion due to the Sm doping.