Understanding and Tailoring Magnetic Interactions at the Interfaces of Magnetic Nanostructures

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

Technical This 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-Technical As 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.