Glover Stephanie E, Saerbeck Thomas, Achinuq Barat, Ghasemi Arsham, Kepaptsoglou Demie, Ramasse Quentin M, Yamada Shinya, Hamaya Kohei, Hase Thomas P A, Lazarov Vlado K, Bell Gavin R
Department of Physics, University of Warwick, Coventry, CV4 7AL, United Kingdom.
Institut Laue Langevin, 38042 Grenoble Cedex 9, France.
J Phys Condens Matter. 2018 Feb 14;30(6):065801. doi: 10.1088/1361-648X/aaa4c8.
The depth-resolved chemical structure and magnetic moment of [Formula: see text], thin films grown on Si(1 1 1) have been determined using x-ray and polarized neutron reflectometry. Bulk-like magnetization is retained across the majority of the film, but reduced moments are observed within 45[Formula: see text] of the surface and in a 25[Formula: see text] substrate-interface region. The reduced moment is related to compositional changes due to oxidation and diffusion, which are further quantified by elemental profiling using electron microscopy with electron energy loss spectroscopy. The accuracy of structural and magnetic depth-profiles obtained from simultaneous modeling is discussed using different approaches with different degree of constraints on the parameters. Our approach illustrates the challenges in fitting reflectometry data from these multi-component quaternary Heusler alloy thin films.
利用X射线和极化中子反射测量法测定了生长在Si(1 1 1)上的[化学式：见原文]薄膜的深度分辨化学结构和磁矩。在薄膜的大部分区域都保留了块状磁化，但在距表面45[化学式：见原文]以内以及25[化学式：见原文]的衬底界面区域观察到磁矩减小。磁矩减小与氧化和扩散引起的成分变化有关，通过使用带有电子能量损失谱的电子显微镜进行元素剖析进一步对其进行了量化。使用对参数具有不同约束程度的不同方法讨论了从同步建模获得的结构和磁深度剖面的准确性。我们的方法说明了拟合这些多组分四元赫斯勒合金薄膜的反射测量数据时所面临的挑战。
