Transport properties and magnetoresistance in CoNb1−xMnxSb half-Heusler alloys with a low temperature localization
- 作者：Sh ; ong Li ; Meimei Liu ; Zhicheng Zhang ; Zhonglin Lu ; Yingbin Lin ; Liya Lü ; Wenqin Zou ; Youwei Du
- 关键词：A. Half Heusler alloy ; D. Transport properties ; D. Magnetotransport properties ; D. Spin-dependent scattering
- 刊名：Solid State Communications
- 出版年：2007
- 期刊代码：101_00381098
- 类别：ms
- 出版时间：February 2007
- 卷：141
- 期：8
- 页码：449-452
- 文件大小：474 K
摘要
The transport properties and magnetoresistance of half-Heusler CoNb1−xMnxSb (x=0.0–1.0) alloys have been investigated between 2 and 300 K. In this temperature range, a metallic conductivity has been observed for the alloys with higher (x=1.0) and lower (x=0.0–0.2) Mn contents. However, the middle Mn content alloys (x=0.4–0.8) exhibit non-metallic conductive behavior. Their temperature dependence of resistivity undergoes a Mott localization law ρ=ρ0exp(T0/T)p (p=1/4) rather than a thermal excitation regime ρ=ρ0exp(Ea/kT) at low temperature (). The localization can be attributed to atomic and magnetic disorder. Resistivity peaks from 25 to 300 K were also observed for these alloys. Magnetotransport investigation reveals that these resistivity peaks result from localization effect as well as spin-disorder scattering.