Abstract: The sample of manganite perovskite oxide La0.7Ca0.2Sr0.1MnO3 has been prepared by solution combustion synthesis. The synthesized sample has been pelletized and further sintered at 8000C for 8 hours. The XRD pattern reveals that the samples are of single phase nature with orthorhombic structure and the diffraction patterns can be indexed with the pbnm space groups. The crystallite sizes calculated from broadening of XRD peaks using Scherrer's formula were about 18 nm. Resistivity measurements were performed in the temperature range 2K under 3, 5, 10 and 14 T field using PPMS. Magnetoresistance shows a shift in metal-insulator transition temperature from ~213 K at zero field to ~250 K at 14T. MR value decreases as the temperature increases and at 300 K maximum value of MR is found to be ~ 22% for an applied field of 14 T. MR of ~ 28% is observed at 230 K. MR of ~ 35% is observed at 150 K in an applied field of 14 T and MR has negative sign.
Keywords: Manganites, Perovskite, Magnetoresistance, Magnetotransport and Combustion Synthesis.
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