Magnetoresistive properties of the La0.7Ce0.3MnO3 bulks and epitaxial thin films

The La0.7Ce0.3MnO3+delta compounds and epitaxial thin films were fabricated by the solid-state reaction and the pulse laser deposition methods, respectively. The XRD patterns, the temperature dependence of resistivity, the temperature dependence of the magnetization and the temperature dependence of the heat specific of these samples were measured. We thought the sample La0.7Ce0.3MnO3+delta was electron doped system. Both the bulk sample and the thin film sample show paramagnetic-ferromagnetic transition and metal-insulator transition phenomena. In addition, both them display a prominent giant magnetoresistance (CMR) around the Curie temperature, However, the temperature of paramagnetic-ferromagnetic transition and CMR between them was different.