Magnetic Phenomena in Ultra-thin Films and at Thin-film Interfaces

这个凝聚态物理项目利用最近发展起来的两种独立但互补的技术来研究和表征超薄膜和薄膜界面上的磁性。第一种是利用一种特殊的真空沉积能力，在没有暴露在空气中的情况下，对新沉积的薄膜中的磁传输进行原位表征。第二种方法利用沉积高质量的无针孔介质来制造介质间距足够薄(50A)的电容器，以确保导电磁极中磁排向自旋的贡献将主导测量的电容。这些技术对表面几埃范围内的磁性特别敏感，将被用于研究元素材料(例如，锰、铁、铬)和新型材料(例如，稀磁半导体、锰酸盐、Ruthenate)。如果成功，这个项目将巩固增加原位薄膜研究和磁电容作为新工具的前景，不仅可以提高我们对界面和表面磁性的理解，而且还有助于为磁电子和纳米科学应用设计界面。在追求这些目标的过程中，本科生、研究生和博士后将在学术、工业或政府环境中获得宝贵的技术和分析技能。这种培训将通过在学术期刊上发表和传播研究成果、参加科学会议和参与跨学科合作来加强。薄膜纳米结构中的磁性强烈地由表面和界面主导。随着薄膜厚度的减小，薄膜两面界面的影响开始占主导地位，磁性现象也受到密切的影响。这一个人研究人员奖利用两种最近开发的技术来研究和表征超薄膜和薄膜界面上的磁性，这两种技术是分开但相互补充的。第一种技术采用了一种特殊的真空沉积能力，用于在不暴露于空气的情况下原位表征新沉积的薄膜的磁性。第二种方法是利用沉积高质量的介质来制造电容器，这种电容器对导电磁极表面的磁排向自旋的存在很敏感。将研究铁磁半导体等新材料。如果成功，这个项目将巩固增加原位薄膜研究和磁电容作为新工具的前景，不仅可以提高我们对界面和表面磁性的理解，而且还有助于为磁电子和纳米科学应用设计界面。在追求这些目标的过程中，本科生、研究生和博士后将在学术、工业或政府环境中获得宝贵的技术和分析技能。这一培训将通过参与跨学科协作而得到加强。

This condensed matter physics project utilizes two recently developed techniques, which are separate but complementary, to study and characterize magnetism in ultra thin films and at thin-film inter-faces. The first employs a specialized vacuum deposition capability for in situ characterization of magnetotransport in freshly deposited thin films without exposure to air. The second utilizes the deposition of high quality pinhole-free dielectrics to fabricate capacitors with dielectric spacing thin enough (50 A) to assure that the contribution from magnetically aligned spins in the conducting magnetic electrodes will dominate the measured capacitance. These techniques, which are uniquely sensitive to the presence of magnetism within a few angstroms of the surface, will be used to study both elemental (e.g., Mn, Fe, Cr) and novel (e.g., dilute magnetic semiconductors, manganites, ruthenates) materials. If successful, this project will solidify the prospects of adding in situ thin-film studies and magnetocapacitance as new tools not only to in-crease our understanding of magnetism at interfaces and surfaces but also to facilitate the engineering of interfaces for magneotelectronic and nanoscience applications. In pursuing these objectives, undergraduate students, graduate students and postdocs will acquire valuable technical and analytical skills for careers in academic, industrial or government settings. This training will be enhanced by the publication and dissemination of research results in scholarly journals, par-ticipation in scientific conferences, and participation in interdisciplinary collaborations.Magnetism in thin-film nanostructures is strongly dominated by surfaces and interfaces. As the thickness of a thin film decreases, the influence of the interfaces at the film's two surfaces begins to dominate, and magnetic phenomena become intimately affected. This individual investigator award utilizes two recently developed techniques, which are separate but complementary, to study and characterize magnetism in ultra thin films and at thin-film interfaces. The first of these techniques employs a specialized vacuum deposition capability for in situ characterization of the magnetic properties of freshly deposited thin films without exposure to air. The second utilizes the deposition of high quality dielectrics to fabricate capacitors that are sensitive to the presence of magnetically aligned spins at the surface of conducting magnetic electrodes. Novel materials such as ferromagnetic semiconductors will be studied. If successful, this project will solidify the prospects of adding in situ thin-film studies and magnetocapacitance as new tools not only to in-crease our understanding of magnetism at interfaces and surfaces but also to facilitate the engineering of interfaces for magneotelectronic and nanoscience applications. In pursuing these objectives, undergraduate students, graduate students and postdocs will acquire valuable technical and analytical skills for careers in academic, industrial or government settings. This training will be enhanced by participation in interdisciplinary collaborations.