Transport and magnetic properties in ferromagnetic manganese-oxide thin   films
  The transport and magnetic properties in ferromagnetic manganese-oxide thin films are studied based on the model of the coupling between the mobile d-electrons and the core spins in Mn ions. The spontaneous magnetization and the resistivity are obtained for various magnetic fields and temperature. The resistivity in absence of magnetic field and the magnetoresistance exhibit maxima near the Curie temperature, the applied magnetic field moves the position of the resistivity peak to high temperature and suppresses the peak value, which agree with the experimental results. The Hall resistivity is predicted to exhibit maximum near the Curie point. The pressure effect of the magnetoresistance can also be explained qualitatively in this mechanism. The colossal magnetoresistance in ferromagnetic manganese-oxide thin films is attributed to the spin-correlation fluctuation scattering and the low dimensional effect. 
Liang-Jian Zou, X. G. Gong, Qing-Qi Zheng and C.Y. Pan (Institute of   Solid State Physics, Academia Sinica, Hefei, China)