Co原子浓度对Co-Mn-Si薄膜各向异性磁电阻及半金属性的影响  

The influence of Co concentration on the anisotropic magnetoresistance and half-metallicity in epitaxial Co-Mn-Si Heusler films

作　　者：杨辅军[1,2] 康泽威 姚军[2] 李继辉[2] 肖君[1,2] 陈晓琴[1,2] 

机构地区：[1]湖北大学有机化工新材料湖北省协同创新中心,武汉430062 [2]湖北大学物理与电子科学学院,武汉430062

出　　处：《中国科学：技术科学》2015年第4期389-395,共7页Scientia Sinica(Technologica)

基　　金：国家自然科学基金(批准号:11274101);日本学术振兴会海外研究员项目(编号:P09295)资助

摘　　要：向原子比为2:1:1的Co-Mn-Si合金薄膜中掺杂Co原子,试图发现Co-Mn-Si合金薄膜半金属性的变化规律.通过制备系列不同成分Co-Mn-Si合金薄膜,并测试薄膜的各向异性磁电阻比.结果发现制备的Co50Mn Si薄膜具有良好的B2结构,杂质及缺陷数量少(剩余电阻比大),各向异性磁电阻比为负值,从而具有良好的半金属属性.随着Co原子浓度的增加,Co-Mn-Si薄膜B2结构取向度降低,剩余电阻比减小,各向异性磁电阻比增大,其半金属属性随Co原子浓度的增加被逐渐破坏.Systematic Co-Mn-Si films have been prepared by changing the Co atomic concentration. Co50MnSi films were found to be good B2 ordering, the small amount of impurities and defects （large RRR value） and negative anisotropic magnetoresistance. With increasing Co concentration, the B2 ordering and RRR value decrease and anisotropic magnetoresistance increases in Co-Mn-Si films. Due to the good half-metallicity of Co50MnSi films （it is reported that EG = 0.4-0.6 eV）, Co70 MnSi films still show negative anisotropic magnetoresistance ratio although the increasing of Co concentration will deteriorate the half-metallicity of Co-Mn-Si films.

关 键 词：半金属 哈斯勒合金 各向异性磁电阻 

分 类 号：TB383.2[一般工业技术—材料科学与工程]