报告主题：
Absolute Determination of Optical Constants by a Direct Physical Modeling of Reflection Electron Energy Loss Spectra
报告人：丁泽军 教授
时间：2016年7月18日(周一) 下午 15:00
地点：教十一大楼318会议室
邀请人：田鹤 研究员
摘要:
Monte Carlo simulation method is a powerful theoretical tool for study of electron-solid interaction. We have developed the updated Monte Carlo models and applied them to surface electron spectroscopy techniques. In this talk I will present an absolute extraction method of optical constants of metal from measured reflection electron energy loss (REELS) spectra with the help of the recently developed reverse Monte Carlo technique. The method is established on a direct physical modeling of electron elastic scattering and electron inelastic scattering near the surface region where the surface excitation becomes important to fully describe the spectrum loss feature intensity in relative to the elastic peak intensity. An optimization procedure of oscillator parameters appeared in the energy loss function for describing electron inelastic scattering due to the bulk- and surface-excitationswas performed with the simulated annealing method by a successive comparison between the measured and Monte Carlo simulated REELS spectra. The optical constants of several metals were deduced from the REELS spectra measured. The validity of the present optical data has been verified with the f- and ps-sum rules. Finally, I will breifly introduce the Monte Carlo simulation applied to linewidth determination by CD-SEM for international standarization.
报告人介绍：
丁泽军 教授1982年于中国科技大学物理系本科毕业，1990年于日本大阪大学应用物理系获博士学位，2000年获国家杰出青年科学基金项目，现为中国科技大学物理系和微尺度物质科学国家实验室教授。主要从事电子束与材料相互作用的计算模拟研究，以及表面电子能谱学和扫描电子显微学方面的国际标准化工作。
