Low Temperature Scanning Tunneling Microscope Studies of Magnetic Nanostructures

9971690 Crommie这个凝聚态物理项目将使用超高真空低温扫描隧道显微镜（STM）研究磁性纳米结构的特性。STM将用于探测单个磁性原子的局部电子结构，以及在干净、特征良好的金属表面上原子制造的磁性纳米结构。STM光谱将探测传导电子之间的相互作用和过渡金属吸附物的局部d-能级。这种相互作用决定了单个杂质原子的磁性，并且还导致合作的电子行为，正如近藤效应中所示。电子行为的趋势将研究不同的吸附物原子从3D，4D和5D周期表的行。将研究温度变化和外加磁场的影响。原子操纵将被用来改变磁性吸附物原子之间的间距，也组装磁性纳米结构原子。还将努力使用非弹性隧穿光谱作为人工制造的纳米结构的磁激发光谱的探针。这项工作将提供有关磁性纳米结构的几个理论预测的实验测试。该研究为本科生，研究生和博士后学生在基础和技术意义的领域提供了良好的培训。单个原子的操纵是材料科学当前的前沿之一。这个凝聚态物理项目的目的是更好地了解表面磁性纳米结构的行为。磁性表面和界面现象目前在数据存储行业中有重要的应用，对微观磁性行为的理解的增加应该会影响这一应用和其他应用。该研究将使用超高真空低温扫描隧道显微镜（STM）研究磁性纳米结构的特性。该仪器将用于探测单个磁性原子的局部电子结构，以及在清洁、表征良好的金属表面上原子制造的磁性纳米结构。原子操纵将被用来改变磁性吸附物原子之间的间距，也组装磁性纳米结构原子。原子操纵提供了一种全新的方法来可控地测量磁性原子之间的相互作用效应，并有望在原子尺度磁性物体的实验研究中开辟一个新的领域。还将努力使用非弹性隧穿光谱作为人工制造的纳米结构的磁激发光谱的探针。从这个项目中获得的基础知识应该提供了一个有用的一步，在纳米尺度上控制凝聚态系统的电子和磁性的目标。这项研究的结果也应该有助于理解其性质取决于组成纳米结构（如颗粒状磁性材料）的大规模系统。该研究为本科生，研究生和博士后学生在基础和技术意义的领域提供了良好的培训。单个原子的操纵是材料科学当前的前沿之一。***

9971690CrommieThis Condensed Matter Physics project will study the properties of magnetic nanostructures using an ultra-high vacuum cryogenic scanning tunneling microscope (STM). The STM will be used to probe the local electronic structure of individual magnetic atoms and atomically fabricated magnetic nanostructures on clean, well-characterized metal surfaces. STM spectroscopy will probe the interaction between conduction electrons interact and the localized d-levels of transition metal adsorbates. Such interactions determine the magnetism of individual impurity atoms, and also lead to cooperative electronic behavior, as seen in the Kondo effect. Trends in electronic behavior will be studied for different adsorbate atoms from the 3d, 4d, and 5d rows of the periodic table. The effects of temperature variation and an applied magnetic field will be investigated. Atomic manipulation will be used to vary the spacing between magnetic adsorbate atoms and also to assemble magnetic nanostructures atom by atom. Efforts will also be made to use inelastic tunneling spectroscopy as a probe of the magnetic excitation spectra of artificially fabricated nanostructures. The work will provide an experimental test of several theoretical predictions concerning magnetic nanostructures. The research provides excellent training for undergraduate, graduate and post-doctoral students in areas of both fundamental and technological significance. The manipulation of individual atoms is one of the current frontiers in materials science. %%%The purpose of this Condensed Matter Physics project is to gain a better understanding of the behavior of magnetic nanostructures at surfaces. Magnetic surface and interface phenomena currently have important applications in the data storage industry, and an increased understanding of microscopic magnetic behavior should impact this and other applications. The research will study the properties of magnetic nanostructures using an ultra-high vacuum cryogenic scanning tunneling microscope (STM). This instrument will be used to probe the local electronic structure of individual magnetic atoms and atomically fabricated magnetic nanostructures on clean, well-characterized metal surfaces. Atomic manipulation will be used to vary the spacing between magnetic adsorbate atoms and also to assemble magnetic nanostructures atom by atom. Atomic manipulation allows a fundamentally new way of controllably measuring interaction effects between magnetic atoms, and promises to open a new regime in the experimental study of atomic-scale magnetic objects. Efforts will also be made to use inelastic tunneling spectroscopy as a probe of the magnetic excitation spectra of artificially fabricated nanostructures. The fundamental knowledge gained from this project should provide a useful step toward the goal of controlling the electronic and magnetic properties of condensed matter systems at the nanometer lengthscale. Results from this study should also be helpful in understanding larger-scale systems whose properties depend on constituent nanostructures (such as granular magnetic materials). The research provides excellent training for undergraduate, graduate and post-doctoral students in areas of both fundamental and technological significance. The manipulation of individual atoms is one of the current frontiers in materials science. ***