Phase Transitions and Materials Interfaces at the Nanoscale

技术概述：这项工作得到了材料研究部的固态和材料化学计划以及化学部的化学测量和成像计划的支持。该项目与理解纳米级固体和材料性质以及化学和物理过程的时空成像有关。具体而言，重点是：(A)研究原子尺度下的界面；(B)纳米尺度上的相变研究；(C)开发新的显微镜和衍射技术，以研究固体表面和块体上化学修饰和组装的层的结构和动力学。这些技术包括会聚光束和近场成像的应用，将被研究的分子、界面和本体系统的例子数不胜数。非技术概述：在一个多世纪的发展中，最重要的科学成就之一是观察原子并捕捉其在物质中的运动。这样的观测使理解物质的行为并在原子尺度上控制它成为可能。电子成像的发展代表了这一提议在空间和时间上的重点，使人们能够直接可视化复杂物质的功能，从纳米技术应用中的材料设计到蛋白质在阿尔茨海默氏症等疾病中的不当行为。多年来，加州理工大学的这个小组拥有300多名研究生、博士后研究员和来访助理，其中大多数人现在处于领先的学术、工业和教育职位。这一指导和推动最先进技术的传统预计将在加州理工学院的PI小组中继续下去。

TECHNICAL SUMMARY:This work is supported by the Solid State and Materials Chemistry program in the Division of Materials Research and the Chemical Measurement and Imaging program in the Division of Chemistry. The project is pertinent to the understanding of nanoscale solid-state and materials properties and to space-time imaging of chemical and physical processes. Specifically, the focus is on: (a) studies of interfaces with atomic-scale resolution; (b) studies of phase transitions at the nanoscale; and (c) development of novel microscopy and diffraction techniques to examine structure and dynamics of chemically-modified and assembled layers on solid surfaces and in bulk. These techniques include applications of convergent-beam and near-field imaging and the examples of molecular, interfacial, and bulk systems to be studied are numerous.NON-TECHNICAL SUMMARY:In over a century of developments, one of the most significant achievements in science is the ability to observe atoms and to capture their motion in matter. Such observations make it possible to understand the behavior of matter and to control it at the atomic scale. The development of imaging with electrons, which represents the focus of this proposal, in space and time, enables direct visualization of the function of complex matter, from materials design in nanotechnology applications to the mis-behavior of proteins in diseases such as Alzheimer's. The group at Caltech has had over the years more than 300 graduate students, post-doctoral fellows, and visiting associates, the majority of whom are now in leading academic, industrial, and educational positions. This tradition of mentoring and advancing the state of the art in technology is expected to continue in the group of the PI at Caltech.