| The studies on transition-metal oxides with Perovskite structure were started in1950’s. As a kind of giant magnetoresistance material, manganese oxides with Perovskite structure show many different characters, for example metal-insulator transition induced by magnetic field or light, charge ordering, orbital ordering and phase separation etc. Nowadays these all are focus of science research. Thus further study on the micromechanism of the giant magnetoresistance effete will help condensed matter physics to develop.Using RF magnetron sputtering and annealed at different temperatures, A series of La0.9Sb0.1MnO3(LSMO) films have been grown on (100) LaAlO3single crystal substrates. The thin films were characterized by X-ray diffraction (XRD), atomic force microscope (AFM). The results show that the LSMO films annealed at temperature in range of800℃～900℃have a single-phase with a pseudo-cubic perovskite structure. The crystal grain density and crystal grain size in thin film have great changes with annealing temperature changing. Magnetoresistance of the thin film annealed at900℃arrives at about33.1%when the temperature is at300K and the magnetic field is at1.5T.A series of rare-earth manganite perovskite polycrystal samples of (La1-xREx)0.9Sr0.1MnO3(RE=Nd, Tb, Ce, Pr) were prepared by solid state reaction in the air. Properties of samples were measured by x-ray diffractometer (XRD), the infrared absorption, vibrating sample magnetometry (VSM). When Mn in B site of matrix La0.9Sb0.1MnO3is partly replaced by Ti, a series of La0.9Sb0.1Mn1-XTiXO3(X=0,0.05,0.10,0.15,0.20) were obtained. Their infrared and magnetic properties were studied. |
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