Magnetic and Electronic Properties of Magnetic Nanostructures

本论文主要研究磁性纳米结构中的自旋-电荷关联。对于层状薄膜，我们将把我们的研究从单量子阱系统扩展到双量子阱系统。单层中的量子波态会导致磁层间耦合。两个量子波之间的相互作用有望产生新的磁效应。对于阶梯薄膜，我们将使用纳米级的原子台阶来横向调制纳米级的2D薄膜。在过去的十年中，层状结构的研究取得了巨大的成就。2D薄膜的横向调制应该进一步缩小维度以产生新的性质。应用球形衬底的新思想，系统地控制台阶取向和台阶密度。所有样品将采用分子束外延(MBE)生长，并用反射高能电子衍射(RHEED)、低能电子衍射(LEED)、俄歇电子能谱(AES)和扫描隧道显微镜(STM)进行表征。用角度分辨光电子能谱(ARPES)测量纳米结构的电学性质，用表面磁光克尔效应(Smoke)技术测量薄膜的磁性。参与该项目的研究生将接受利用尖端技术进行基本实验技术的培训。信息存储技术的小型化已经达到了纳米级的物理过程主导存储材料的整体性能的阶段。这种快速的发展对理解纳米结构中的材料特性的基础研究提出了挑战。这一提议的目的是深入了解磁性材料中随着尺寸接近极限纳米长度尺度时材料性质的变化。为了实现这一目标，分子束外延(MBE)将在原子水平上控制分子束外延(MBE)构建明确的磁性纳米结构，并利用角度分辨光电子能谱(ARPES)、扫描隧道显微镜(STM)和表面磁光克尔效应(Smoke)等最新技术进行研究。将研究纳米结构中电子的量子限制，以探索其在新的磁性中的作用。该项目的成功不仅对理解低维磁学具有重要意义，而且对磁学技术的发展也具有重要意义。参与该项目的研究生将接受使用尖端技术进行基本实验技术的培训。这项培训将为他们在两个学院的一系列职业生涯做好准备

This research is focused on the spin-charge correlation in magnetic nanostructures. For layered films, we will extend our research from single quantum well (QW) system to double QW system. QW states in a single layer can result in the magnetic interlayer coupling. Interaction between two QWs is expected to generate new magneto phenomena. For stepped films, we will use nanometer-sized atomic steps to laterally modulate 2D thin films at nanometer scale. Great achievements have been made in layered structures in the last decade. Lateral modulation of a 2D thin film should further shrink the dimensionality to generate new properties. New idea of spherical substrate will be applied to control the step orientation and the step-density in a systematic way. All samples will be grown by Molecular Beam Epitaxy (MBE) and characterized by Reflection High-Energy Electron Diffraction (RHEED), Low-Energy Electron Diffraction (LEED), Auger Electron Spectroscopy (AES), and Scanning Tunneling Microscopy (STM). Electronic properties of the nanostructures will be measured by Angle Resolved Photoemission Spectroscopy (ARPES) and the magnetic properties of the films will be measured by Surface Magneto-Optic Kerr Effect (SMOKE) technique. Graduate students involved in the project will receive training in fundamental experimental techniques using cutting edge technology.The miniaturization of of information storage technology has reached a stage that physical processes at the nanometer scale dominate the overall properties of the storage materials. This rapid development challenges fundamental research to understand materials properties in nanostructures. The goal of this proposal is to gain a deep understanding on how materials properties change as the size approaches the ultimate nanometer length scale in magnetic materials. To realize this goal, well-defined magnetic nanostructures will be built by Molecular Beam Epitaxy (MBE) with a control at the atomic level, and investigated with state-of-the-art techniques such as Angle Resolved Photoemission Spectroscopy (ARPES), Scanning Tunneling Microscopy (STM), and Surface Magneto-Optic Kerr Effect (SMOKE), etc. Quantum confinement of electrons inside the nanostructures will be studied to explore its role in new magnetic properties. Success of this project will be important not only to the understanding of low-dimensional magnetism, but also to the development of magnetic technology. Graduate students involved in the project will receive training in fundamental experimental techniques using cutting edge technology. This training will prepare them for a range of careers in both academe