NIRT: FRG: Collective and Quasiparticle Properties of Nanocrystals and Nano-Arrays

点击翻译按钮获取中文摘要

A fundamental competition between order and disorder lies at the heart of materials science and technology. Interactions between atoms or electrons spaced sub nanometer apart can lead to collective organization into states with long-range order. Order in electronic states gives rise to physical consequences such as magnetism, ferroelectricity and superconductivity. In bulk materials, the collective electronic properties exhibit a characteristic length scale called the coherence length, which corresponds to the minimum grain size in superconductors, and in ferromagnets the domain wall width. These length scales generally exceed or are comparable to geometrical parameters of nanostructured materials. For these reasons nanostructured materials represent an important new frontier for the study of collective electronic behavior. This interdisciplinary research team will study the physical consequences of nanometer-size dimensions on collective and independent electron properties in individual nanocrystals and in controlled nanocrystal arrays. It is unique in the combination of expertise in materials synthesis, materials characterizations and theory that has been brought together at a single institution. It also forges a close partnership with one leading company in information technology and two foreign institutions. Educationally, this NIRT will help lead the campus-wide initiative at UT Austin for training the next generation of scientists in nanoscience through the integration of research and education and a strong partnership with the newly established Center of Nano- and Molecular Science and Techology. It integrates diversity by actively recruiting graduate students in minority groups. It further reaches out to K-12 education in the Austin area. This interdisciplinary program brings together expertise in advanced synthesis of metal and semiconductor nanostructures, expertise in nanoscale characterizations of structural, electronic, transport, optical and magnetic properties, and expertise in mesoscopic and many-body condensed matter theory, working together in a single institution to explore the physical consequences of nanometer-size dimensions on collective and independent electron properties in individual nanocrystals and in controlled nanocrystal arrays. Of particular interests are ferromagnetic, superconducting, and normal metal nanocrystals, and ferromagnetic, semimagnetic, and normal semiconductor quantum dots. In ferromagnetic and superconducting systems the emphasis to date has been on the collective properties that underlie, for example, the use of ferromagnets for information storage and the potential use of small superconductors as quantum-bits. As these particles become smaller, the physics of the magnetic anisotropy barriers essential for information storage will be altered, and superconductivity will be destroyed, respectively. This regime is a frontier for fundamental physics and for materials physics and chemistry, and will be the focus of this research program. This research team also forges a close partnership with one leading company in information technology and two foreign institutions. It will strengthen educational and training efforts at UT Austin in nanoscience and nanotechnology by designing a new curriculum that removes barriers between current disciplinary specialization in different majors and provides an excellent training ground for the future generation of scientists in nanoscale science and technology.