Milli-Electron Volt Energy Resolution Photoemission Studies of Solids

固体的毫电子伏能量分辨率光电发射研究

• 批准号: 9218706
• 负责人: Eric Jensen
• 金额: $ 27万
• 依托单位: Brandeis University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-03-01 至 1997-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9218706&HistoricalAwards=false
• 关键词: Milli; Electron; Volt; Energy; Resolution

Very high energy resolution (less than 5meV at count rates of 1kHz) photoemission studies of solids at low temperatures will be undertaken on a recently built instrument. These parameters are a significant improvement over previously published work on solid samples, and allows photoelectron spectroscopy to make contact with other experimental methods that study excitations with energies of order kT. Several specific experiments are proposed: Studies of the effects of the electron-phonon interaction on Fermi edges in angle integrated spectra, and on individual surface state dispersion at small binding energy in wide band metals such as copper will be undertaken; this will yield detailed information about the interaction between electrons and phonons at and near solid surfaces. Studies of emission from phosphorus donor levels in silicon for concentration ranges near the metal/insulator critical concentration will determine the one electron density of states and aid in understanding the competition between correlation and disorder in driving this transition. Studies of emission (peak dispersion and line shape) and of the band-gap in conventional and high temperature superconductors will help to determine the mechanism of superconductivity in these materials. %%% The purpose of this research is to bring the power and discrimination of a newly developed high resolution photoelectron spectrometer to bear on a number of current problems in materials physics. The improved resolution could impinge strongly on technological fields such as superconductivity and semiconductor device operation, as well as in various related areas of more fundamental interest. This research will extend the energy resolution of photoelectron spectroscopy by about an order of magnitude, permitting detailed studies of the electrons responsible for device operation. In particular, metal/insulator transitions in semiconductors, the origin of the energy gap in high temperature and conventional superconductors, and the interaction between electrons and atomic vibrations in more ordinary materials will be investigated.

极高的能量分辨率（在1 kHz的计数率下小于5 meV） 低温下固体的光电发射研究将是 在最近建造的仪器上进行。 这些参数是 与以前发表的关于固体的工作相比有了显著的改进 样品，并允许光电子能谱，使接触 其他研究能量为 命令kT。 提出了几个具体的实验： 电子-声子相互作用对费米边的影响 角积分谱，并对个别表面状态 宽带金属中小结合能的色散， 铜将进行;这将产生详细的信息 电子和声子之间的相互作用 固体表面 磷施主能级发射的研究 在金属/绝缘体附近的硅中形成浓度范围 临界浓度将决定一个电子密度 国家和援助之间的竞争理解相关性 and disorder无序in driving驱动this transition过渡. 排放研究（峰值） 色散和线形状）和带隙， 高温超导体将有助于确定 这些材料中的超导机制。 %%% 这项研究的目的是把权力和 一种新的高分辨光电子的鉴别 光谱仪对材料中的一些当前问题的影响 物理学 改进的分辨率可能会对 超导和半导体等技术领域 设备操作，以及在各种相关领域的更多 根本利益。 这项研究将扩大能源 光电子能谱的分辨率约为 量级，允许详细研究电子负责 用于设备操作。 特别是，金属/绝缘体转变 在半导体中，高温下能隙的起源 和传统超导体之间的相互作用 在更普通的材料中，电子和原子振动将被 研究了