Ferromagnetism at the interfaces of antiferromagnetic FeRh epilayers
Ferromagnetism at the interfaces of antiferromagnetic FeRh epilayers
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DOI：
10.1103/physrevb.82.184418
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发表时间：
2010-11-12
影响因子：
3.7
通讯作者：
Langridge, S.
中科院分区：
文献类型：
--
作者：
Fan, R.;Kinane, C. J.;Langridge, S.
用极化中子反射法研究了FeRh外延层的纳米磁性结构。通过分子束外延在MgO（001）衬底上生长标称厚度为500埃的外延膜，并用20埃的MgO覆盖。随着温度的升高，FeRh薄膜表现出从反铁磁（AF）态到铁磁（FM）态的明显转变。令人惊讶的是，即使在低于膜的AF-FM转变温度80 K的温度下，膜也具有FM矩。我们已经量化了这个FM时刻的大小和空间范围，其被限制在接近顶部和底部界面的FeRh的60-80埃内。这些界面FM层解释了以前在厚度为100 μ m的薄膜中观察到的不寻常的效应。
The nanoscale magnetic structure of FeRh epilayers has been studied by polarized neutron reflectometry. Epitaxial films with a nominal thickness of 500 angstrom were grown on MgO (001) substrates via molecular-beam epitaxy and capped with 20 angstrom of MgO. The FeRh films show a clear transition from the antiferromagnetic (AF) state to the ferromagnetic (FM) state with increasing temperature. Surprisingly the films possess a FM moment even at a temperature 80 K below the AF-FM transition temperature of the film. We have quantified the magnitude and spatial extent of this FM moment, which is confined to within similar to 60-80 angstrom of the FeRh near the top and bottom interfaces. These interfacial FM layers account for the unusual effects previously observed in films with thickness