Impact of copper substitution on the magnetism and transport properties of La0.7Ba0.25Nd0.05Mn1−Cu O3 (x = 0, 0.03, 0.05, and 0.07)

The impact of copper substitution on the structural, morphological, and magnetic properties, as well as the transport properties of La0.7Ba0.25Nd0.05Mn1−xCuxO3 (x = 0, 0.03, 0.05, and 0.07), has been investigated. Structural investigation results revealed that the samples crystallized in a rhombohedral system with the R3c space group without any detectable impurities. Morphological investigation showed that copper substitution significantly improved the grain size of the sample. Temperature dependence of magnetization measurement indicated that all samples underwent ferromagnetic to paramagnetic transition at the Curie temperature (TC). As copper concentration increased, the Curie temperature, TC, decreased from 302 K, 275 K, 258 K, and 229 K for samples with x = 0, 0.03, 0.05, and 0.07, respectively. Resistivity dependence on temperature measurement discovered that copper substitution significantly affected the overall resistivity of the samples. Additionally, copper substitution also induces a metal–insulator transition. The impact of copper substitution on the transport mechanism of the sample was investigated by fitting it with a suitable mathematical model.