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In recent years, it was found that the perovskite manganite La1-xTxMn03 (T is an alkali metal element, such as of Sr, Ca, Ba, and Pb, etc.) having colossal magnetoresistance (colossal magnetoresistance, CMR) effect, since the magnetic sensor, The high-speed high-density magnetic memory devices and optoelectronic devices have potential applications aroused wide the 'Pan concern. However, from the practical application of this type of giant magnetoresistance material there are still many difficulties, such as: the produce the CMR phenomenon applied magnetic field is very large, usually takes a few Tesla; material magnetoresistance peak appear in the low temperature zone; magnetic resistor a drastic change in a very narrow temperature range, these factors have greatly limited the practical application of such a manganese oxide material. At present, a lot of research work has focused on the alkali metal element is doped at the A site, and the use (LA1-xREx) 1-yTyMnO3 double rare earth structure (where RE is the second rare earth ion), little research, RE = Nd3 prepared The study of the rare earth manganese oxide films has not been reported. Nd3 portion Alternate La3, La0.5-xvNdxSr0.5MnO3 (x = 0.1,0.2,0.3,0.4) the material and La0.4Nd0.1Sr0.5MnO3 film was prepared, the structure of the above-mentioned material and film Transitivity System to obtain meaningful results. By solid state reaction prepared the the perovskite manganite La0.5-xNdxSro.5Mn03 (x = of 0.1, 0.2, 0.3, 0.4) polycrystalline samples. Analysis by X-ray diffraction (XRD), scanning electron microscopy (SEM), the infrared absorption spectrum measurement, microwave absorption, the four probe method by means of the sample structure and nature of the tests. The results show that, when Nd doping amount x lt; 0.3, the sample formed a single phase orthorhombic perovskite structure when x = 0.4, Sample La0.5-xNdxSr0.5MnO3 and Nd203 two, phase composition. The particle morphology of the sample cube to render comparison rule, particle size uniform, With Nd3 concentration increases, the particles gradually smaller, 615cm-1 near the absorption peak and gradually moved to the high-frequency. Nd3 concentration of material magnetoresistance and microwave absorption properties significant impact. RF magnetron sputtering method combined with the post-annealing process LaAlO3 (100) substrate prepared a series of thin film samples La0.4Nd0.1Sr0.5Mn03 (LNSMO). By X-ray diffraction instrument (XRD), atomic force microscopy (AFM), photoelectron spectroscopy (XPS), four-probe method, its structure and nature of the test. The results show that the film temperature range of annealing at 700-900 ℃ to form a single-phase pseudo-cubic perovskite structure. Different annealing temperature to cause the film oxygen content changes and also has a great influence on the grain size. After the 850 ° C annealed film sample was 300K, the magnetic field at room temperature under conditions of 1.5T, a magnetic resistance reached 24.9%.
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