Transport and magnetic properties of La_(0.9)Ce_(0.1)MnO_3 thin films

摘要

The transport and magnetic properties of La_(0.9)Ce_(0.1)MnO_3 epitaxial thin films without observable impurity of CeO_2 on their x-ray diffraction data using pulsed laser deposition method were investigated by varying the oxygen partial pressure and the substrate temperature with the intention being to investigate whether the material is an electron-doped system. The film deposited under the oxygen partial pressure of 1 Pa exhibited the metal-insulator transitionlike peak and ferromagnetic transition around 200 K. Thermopower measurement identified the major carriers within the film to be holes. In addition, decreasing the oxygen partial pressure resulted in not only an increase in the resistivity but also a decrease in the Curie temperature. In fact, these trends on transport and magnetic properties are consistent with general trends of a hole-doped system.