Low-field magnetoresistance in nanosized La0.7Sr0.3MnO3 ÕPr0.5Sr0.5MnO3 composites
نویسندگان
چکیده
Nanosized La0.7Sr0.3MnO3 /Pr0.5Sr0.5MnO3 ~LSMO12xPSMOx) ceramic composites are prepared using solid-sate sintering. Their microstructural, electroand magnetotransport properties are characterized by means of various techniques. It is found that the antiferromagnetic/ferromagnetic coupling between PSMO/LSMO at low temperature and the weak ferromagnetic order of PSMO at high temperature results in enhanced low-field magnetoresistance ~LFMR! of the composites. With increasing temperature up to 250 K the observed LFMR decays more slowly than that for pure LSMO and this behavior may be explained by the spin coupling near boundaries between LSMO and PSMO grains. © 2001 American Institute of Physics. @DOI: 10.1063/1.1350602#
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