Sr离子含量的减少对于La_(0.60)Sr_(0.25)Na_(0.15)MnO_3材料性能的影响

Influence of Sr Deficiency on the Performance of La_(0.60)Sr_(0.25)Na_(0.15)MnO_3

利用溶胶-凝胶法（sol-gel）制备了稀土锰氧化物多晶样品La0.60Sr0.25-xNa0.15MnO3,发现随着Sr离子含量的减少,样品在室温附近庞磁电阻效应有了明显的改善。在1.8 T的磁场下,对于x=0.05的样品,其CMR值在240~320 K的温区范围内均保持在5.3%（±0.2%）,温度稳定性有显著改善。

The perovskite rare-earth manganites polycrystalline samples La0.60Sr0.25-xNa0.15MnO3 were synthesized with sol-gel method. It is found that the magnetoresistance （MR） effect of this kind of material can be remarkably improved by the deficiency of Sr. Under an applied magnetic filed of 1. ST, the MR value of the sample with x= 0. 05 is about 5.3 % （±0. 2%） in the temperature range between 240K and 320K, so that its temperature stability is improved, which is important for the application of this magnetoresistance material.