Electromagnetic transport properties and magnetoresistance of La0.7Ca0.2Sr0.1MnO3–Ag composites prepared by electroless process

A series of bulk polycrystalline La0.7Ca0.2Sr0.1MnO3 (LCSMO)–Ag composites were prepared by electroless plating process and several kinds of physical properties have been studied systemically. According to the results of X-ray diffraction (XRD), scanning electron microscopy (SEM), and electromagnetic transport properties, we can see that Ag-added segregated at the surfaces or interfaces of LCSMO grains. The metal-insulator transition temperature (TP) and Curie temperature (Tc) were almost unchanged but ρ decreased with increasing plating time. We also observed Ag-added can significantly enhance the magnetoresistance (MR) near TP under a low applied field (3000 Oe) and the room temperature MR reached to 35% under 20 kOe, which is encouraging for practical applications. We can suggest that improved grain boundary effect by Ag-added is responsible for the enhancement.

Magnetic field dependence of the MR for the composites at 298 K. The inset is the different silver-plating time dependence of the variation of MR at 2 T.Figure optionsDownload as PowerPoint slide