摘要
采用溶胶一凝胶 (sol gel)法制备了名义组分为La0 6 7Sr0 33-XCuXMnO3(x =0～ 0 33)的多晶样品 ,发现用Cu替代少部分Sr后样品的室温磁电阻比替代前的明显增大。在 1 8T磁场作用下 ,当x =0 15时 ,磁电阻峰值为 2 7 7% ,峰值温度为 30 6K ,当温度低于 30 6K时磁电阻值随温度的升高而增大 ,当温度高于 30 6K时磁电阻值随温度的升高而减小 ;当x =0 1时 ,在 2 95K— 310K温度之间磁电阻值达 19%左右 ,受温度影响很小 ;因此在提高了室温磁电阻值的同时 ,又提高了磁电阻的温度稳定性。这对于该类磁电阻材料的应用具有很大意义。
La 0.67Sr 0.33-XCu XMnO 3 series polycrystalline samples were synthesized by sol-gel method.It is found that the room magnetoresistance (MR)of this kind of material is larger than La 0.67Sr 0.33-XCu XMnO 3.Under an applied magnetic filed of 1.8T,the maximum value of MR is 27.7% for the sample with x0.15 at 306K,and the value of MR increases with increase of temperature below 306K,while decrease with temperature above 306K.The MR vaule of La 0.67Sr 0.33-XCu XMnO 3 is about 19% in the temperature range between 295K and 310K,therefore its temperature stability is better.So not only MR value is increased but also temperature stability of magentoresistance is improved,which is important for the application of this magnetoresistance material.
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2004年第1期102-104,共3页
Journal of Materials Science and Engineering
基金
国家自然科学基金资助项目 (1 0 0 740 1 3)
