摘要
用Dy和Yb部分替代La0.67Ca0.33MnO3中的La使材料的居里温度单调下降.掺Dy使材料的相变温度单调下降,峰值电阻率迅速增大,磁电阻比急剧增大.掺入13％(原子分数)的Dy可使材料的最大磁电阻比增大近40倍.而掺Yb对磁电阻的影响要小得多.用自旋团簇理论可以解释庞磁电阻的形成.
La in La0.67Ca0.33MnO3 has been partially substituted by Dy and Yb. With increasing doping amounts of Dy and Yb, the Curie temperature decreases monotonically. When La is substituted by Dy, the transition temperature decreases monotonically, the peak resistivity increases rapidly, while the magnetoresistance ratio (MR) increases dramatically. The substitution of 13% (atomic fraction) Dy for La increases the MR ratio by almost 40 times. The influence of doping Yb on the MR is very small. The mechanism of colossal MR (CMR) can be explained in terms of spin clusters.
出处
《材料研究学报》
EI
CAS
CSCD
北大核心
2002年第6期565-569,共5页
Chinese Journal of Materials Research
基金
国家重点研究发展规划资助项目G19980613010
国家科技部资助项目
