Transport and magnetic properties in La0.67Ca0.33MnO3 thick films

We present transport and magnetic measurements in thick films of the perovskite La0.67Ca0.33MnO3 on alumina substrates, made by a conventional paint-on method. In our case the temperature dependence of resistance is characterized by the existence of a broad peak (at 180 K) far below the Curie temperature (240K). The samples show a strong ferromagnetism, while the magnetoresistance coefficient exhibits a general diminishing monotonic behavior with the temperature. We discuss these results, considering the magnetic disorder related with possible local variation of the Mn (4+) content and its relation with the transport properties.