Interface structure and magnetism of magnetic tunnel junctions with a Co2MnSi electrode
Interface structure and magnetism of magnetic tunnel junctions with a Co2MnSi electrode
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DOI：
10.1103/physrevb.70.024426
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发表时间：
2004-07
影响因子：
3.7
通讯作者：
J. Schmalhorst;S. Kämmerer;M. Sacher;G. Reiss;A. Hütten;A. Scholl
中科院分区：
文献类型：
--
作者：
J. Schmalhorst;S. Kämmerer;M. Sacher;G. Reiss;A. Hütten;A. Scholl
采用软磁Heusler合金电极（Co_2MnSi/Al+氧化+原位退火/Co_7Fe_3/Mn_83Ir_17），在10 K/10 mV下获得了86%的最大隧道磁阻效应，利用电子和X射线吸收谱研究了其下势垒界面的结构和磁性.等离子体氧化诱导的Mn/Si偏析和氧化物形成在势垒界面处被发现，这导致结的面积电阻积的强烈增加，因为势垒厚度的增大。对于Co2 MnSi厚度等于8 nm或更大，Mn和Co的自旋在界面处的铁磁顺序诱导退火，同时，观察到在界面处的原子有序。的结的温度依赖性的输运性质的结构和磁性的界面特性的影响进行了讨论。
Magnetic tunnel junctions with a magnetically soft Heusler-alloy electrode (Co2MnSi/Al+oxidation+in situ annealing/Co7Fe3/Mn83Ir17) and a maximal tunnel magnetoresistance effect of 86% at 10 K/10 mV are investigated with respect to their structural and magnetic properties at the lower barrier interface by electron and x-ray absorption spectroscopy. A plasma-oxidation-induced Mn/Si segregation and oxide formation at the barrier interface is found, which results in a strongly increased area-resistance product of the junctions, because of an enlarged barrier thickness. For Co2MnSi thickness equal to 8 nm or larger, ferromagnetic order of Mn and Co spins at the interface is induced by annealing; simultaneously, atomic ordering at the interface is observed. The influence of the structural and magnetic interface properties on the temperature-dependent transport properties of the junctions is discussed.