Understanding and Tailoring Magnetic Interactions at the Interfaces of Magnetic Nanostructures

这项凝聚态物理研究将发展对磁性纳米结构中界面和层间相互作用的基本理解。氧化物和金属薄膜将通过原子层控制的分子束外延（MBE）生长，并通过反射高能电子衍射（RHEED）、低能电子衍射（LEED）、俄歇电子能谱（AES）和扫描隧道显微镜（STM）等最先进的技术进行表征。自旋极化低能电子显微镜（SPLEEM）测量的自旋依赖电子反射率揭示了超薄膜的自旋依赖电子结构。利用光电电子显微镜（PEEM）对元素的特定磁畴进行成像，以检索磁界面和层间耦合的影响。磁滞回线也将通过原位表面磁光克尔效应（SMOKE）技术和x射线磁圆二色性（XMCD）进行测量。该研究将涉及研究生和本科生，从而为学生提供基础科学和技术的自然训练。非技术随着材料的尺寸缩小到纳米尺度，电子的电荷和磁场（自旋）可以一致地行为，从而产生对未来信息技术非常重要的独特材料特性。这个凝聚态物理研究项目将对磁性纳米结构中不同材料边界处的电子自旋相互作用有一个基本的了解。这种理解对于开发具有天然材料所不具备的性能的人工结构至关重要。为了实现这一目标，将采用最先进的技术在原子水平上合成和表征材料。研究结果将有助于理解纳米尺度下电子自旋的新行为，并为未来自旋电子学器件的制造提供指导。研究生将接受现代实验技术前沿的培训，这对他们未来在学术、工业和政府工作中的职业生涯至关重要。参与该研究项目的本科生将有机会将课堂知识融入到真正的科学研究中。

TechnicalThis condensed matter physics research will develop a fundamental understanding of interfacial and interlayer interactions in magnetic nanostructures. Oxide and metallic thin films will be grown by Molecular Beam Epitaxy (MBE) with atomic layer control and characterized by the state-of-the-art techniques of Reflection High-Energy Electron Diffraction (RHEED), Low-Energy Electron Diffraction (LEED), Auger Electron Spectroscopy (AES), and Scanning Tunneling Microscopy (STM). Spin-dependent electronic reflectivity measured by Spin-Polarized Low Energy Electron Microscopy(SPLEEM) will reveal spin-dependent electronic structure of the ultrathin films. Element specific magnetic domains will be imaged by Photoemission Electron Microscopy (PEEM) to retrieve the effect of magnetic interfacial and interlayer couplings. Magnetic hysteresis loops will also be measured by in situ Surface Magneto-Optic Kerr Effect (SMOKE) technique and X-ray Magnetic Circular Dichroism (XMCD). The research will involve both graduate and undergraduate students, thus provides a natural training of the students on basic science and technology.Non-TechnicalAs the size of materials is reduced to the nanometer scale, the electrical charge and magnetic field (spin) of electrons can behave coherently to generate unique materials properties that are important to the future information technologies. This condensed matter physics research program will develop a basic understanding of the electron spin interactions at the boundaries of different materials in magnetic nanostructures. This understanding is crucial to the development of artificial structures which consist of properties not available in natural materials. In order to achieve this goal, state-of-the-art techniques will be employed to synthesize and characterize the materials at the atomic level. Result of the research will lead to an understanding of the new behaviors of electron spins at the nanometer scale, and to provide guidance for future spintronics device fabrication. Graduate students will receive training at the cutting edge of modern experimental techniques, which is crucial for their future careers in academic, industrial, and government jobs. Undergraduate students involved in this research program will have a chance of integrate their class room knowledge into the real scientific research.