...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Physical review >Stacking Dependent Disordering Processes In Gd/co/pt(111) Studied With Surface X-ray Diffraction
【24h】

Stacking Dependent Disordering Processes In Gd/co/pt(111) Studied With Surface X-ray Diffraction

机译：表面X射线衍射研究Gd / co / pt（111）中的堆叠相关无序过程

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Disordering processes induced by Gd overlayers on 15 atomic layers thick Co films grown on top of a Pt(111) surface have been studied in situ by surface x-ray diffraction. They have been investigated in two structurally different Co layers deposited at different substrate temperatures: a film grown at 220 K consisting of a mixture of hcp and fcc crystallites plus some disordered stacking, and another one grown at room temperature containing more disorder and fcc crystallites only. Gd induced disordering has been found to be dependent on the structure of the Co film since cubic fcc crystallites are more sensitive to disordering than hexagonal ones. In addition, Gd deposition causes a reduction in about 0.5% in the Co interatomic distance in the layer plane, which arises from relaxation of stress in the film. The stress is mainly concentrated in fcc grains, which are more strained in the film plane than hcp ones. Furthermore, Co grains having the substrate fcc stacking sequence are majority in the Co films, and they are more stable against disordering than the corresponding fcc twin ones, suggesting some kind of long-range interaction stabilizing the majority stacking. These structural modifications induced by the Gd overlayers affect the magnetism of the film, as evidenced by the hysteresis loops measured by magneto-optical Kerr effect, probing the Co magnetization, and by resonant x-ray scattering at the Pt L_(III) edge, sensitive to the Pt magnetization at the Co/Pt interface. It has been found that the Gd overlayer changes the magnetization of the whole Co film, increasing significantly its coercive field for thick enough Gd overlayers and reducing the amplitude of the loops. These changes are compatible with the formation of a disordered Co-Gd alloy with reduced magnetic moment for the Co atoms, and they affect the whole Co film down to the Pt interface. All these results illustrate how surface x-ray diffraction can be used torncharacterize in detail alloying processes happening in thin films of binary systems, especially in those containing heterogeneous mixtures of different phases.
机译：通过表面X射线衍射原位研究了Gd覆盖层在15个原子层厚的Pt（111）表面顶部生长的Co膜上引起的无序过程。已在两个在不同基板温度下沉积的结构不同的Co层中对它们进行了研究：一个在220 K下生长的膜，该膜由hcp和fcc晶体的混合物加上一些无序的堆积组成，另一层在室温下生长的膜仅包含更多的无序和fcc晶体。已经发现，Gd诱导的无序取决于Co膜的结构，因为立方六方立方晶体比六方晶对无序更为敏感。此外，Gd沉积会导致层平面内Co原子间距离减少约0.5％，这是由于薄膜中的应力松弛所致。应力主要集中在fcc晶粒中，与hcp晶粒相比，其在薄膜平面上的应变更大。此外，具有基底fcc堆积顺序的Co晶粒在Co膜中占多数，并且它们比相应的fcc孪晶对杂乱性更稳定，这表明某种远程相互作用可以稳定多数堆积。由Gd覆盖层引起的这些结构修饰会影响薄膜的磁性，这可以通过磁光Kerr效应，探测Co磁化强度以及在Pt L_（III）边缘的共振X射线散射测量到的磁滞回线来证明，对Co / Pt界面上的Pt磁化敏感。已经发现，Gd覆盖层改变了整个Co膜的磁化强度，对于足够厚的Gd覆盖层显着增加了其矫顽场，并减小了环路的幅度。这些变化与无序Co-Gd合金的形成相容，该无序Co-Gd合金的Co原子磁矩减小，并且影响到整个Co膜直至Pt界面。所有这些结果说明了如何使用表面X射线衍射来详细表征二元体系薄膜中发生的合金化过程，尤其是在包含不同相的不均匀混合物的合金化过程中。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号