Magnetoresistance of nanostructured Sr_2FeMoO_6/CeO_2 composites

摘要

(Sr_2FeMoO_6)_(1-x)/(CeO_2)_x composites with nanosized crystallite were prepared by Sr_2FeMoO_6 obtained from the sol-gel method and nanosized CeO_2 powders. The magnetoresistance of composites increase with the CeO_2 increasing. And the MR ratio at 10 K is 1.23%, and 2.48% for the x = 0.05 and 0.2 samples with H = 1 kOe, which are 1.25 times and 2.53 times as large as that for pure Sr_2FeMoO_6, respectively. The enhanced magnetoresistance was attributed to the spin-dependent tunneling at the interface of grain boundaries.