Structural, magnetic and transport properties of Co2FeAl Heusler films with varying thickness
Structural, magnetic and transport properties of Co2FeAl Heusler films with varying thickness
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不同厚度的 Co2FeAl Heusler 薄膜的结构、磁性和输运特性
DOI：
10.1016/j.jmmm.2014.03.028
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发表时间：
2014-08-01
影响因子：
2.7
通讯作者：
Wu, Guangheng
中科院分区：
文献类型：
--
作者：
Wang, Xiaotian;Li, Yueqing;Wu, Guangheng
本文系统地研究了MgO（001）衬底上Heusler合金Co_2FeAl（CFA）外延薄膜的结构、磁性和反常霍尔效应随薄膜厚度的变化。结果表明，CFA薄膜具有面内单轴磁各向异性的高度有序的B2结构。电输运性质揭示了晶格和磁振子散射对纵向电阻率的贡献。独立于膜的厚度，CFA膜的异常霍尔电阻率被发现是由斜散射只占主导地位。此外，反常霍尔电阻率表现出弱的温度依赖性行为，其绝对值随厚度的减小而增大。我们将这种温度不敏感性的异常霍尔电阻率的CFA薄膜中的隧道自旋极化的弱温度依赖性，而厚度依赖性的行为可能是由于界面或自由表面电子态的重要性增加。(C)© 2014 Elsevier B.V.保留所有权利。
We report on a systematic study of the structural, magnetic properties and the anomalous Hall effect, in the Heusler alloy Co2FeAl (CFA) epitaxial films on MgO(001), as a function of film thickness. It was found that the epitaxial CFA films show a highly ordered B2 structure with an in-plane uniaxial magnetic anisotropy. The electrical transport properties reveal that the lattice and magnon scattering contributions to the longitudinal resistivity. Independent on the thickness of films, the anomalous Hall resistivity of CFA films is found to be dominated by skew scattering only. Moreover, the anomalous Hall resistivity shows weakly temperature dependent behavior, and its absolute value increases as the thickness decreases. We attribute this temperature insensitivity in the anomalous Hall resistivity to the weak temperature dependent of tunneling spin-polarization in the CFA films, while the thickness dependence behavioris likely due to the increasing significance of interface or free surface electronic states. (C) 2014 Elsevier B.V. All rights reserved.