CAREER: Photodetachment from Nanometer-Sized Particles

职业：纳米尺寸颗粒的光分离

• 批准号: 9876224
• 负责人: Uwe Kortshagen
• 金额: $ 20万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-04-15 至 2004-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9876224&HistoricalAwards=false
• 关键词: CAREER; Photodetachment; Nanometer; Sized; Particles

This project addresses research on basic properties on nanoparticles and the measurement of current unexplored properties such as photodetachment and photoionization. It is suggested that photodetachment of electrons due to UV radiation is an important, to date neglected effect which can lead to more positively charged particles and that it could explain the fast coagulation growth of particles observed experimentally. An experiment to measure the particle photodetachment cross sections is proposed. Negatively charged particles will be grown in, extracted from a pulsed plasma and sent through a UV photodetachment chamber. An excimer lamp will be used to generate narrow-band UV radiation over a wide wavelength range. An electrostatic analyzer will be used to determine the fraction of particles which have experienced photodetachment. The results may lead to an understanding of particle growth in semiconductor plasmas and possibly may show a way to avoid coagulation growth of "killer particles."The educational plan focuses on creating awareness and transmitting excitement about the research area of plasma processing and nanoparticle research. High school students will get a first hand impression of research through short lectures and laboratory visits. High school teachers will be invited to participate in research activities during the summer and be advised in developing exciting "dusty plasma" related classroom experiments. Undergraduate students will be addressed through course development and development of interactive, computer-based teaching materials. Students will experience the excitement of research by working with a research grade plasma simulation code on "virtual plasmas" and by having the opportunity to compare their results to "real" plasmas in laboratory demonstrations. They will also have the opportunity of direct research involvement through research assistantships, and honors thesis projects. Graduate students will benefit from the program, in particular, through the opportunity of international exchange.

该项目主要研究纳米颗粒的基本性质，以及测量当前未开发的性质，如光剥离和光电离。我们认为，由于紫外线辐射导致的电子光分离是一个重要的，迄今为止被忽视的效应，它可以导致更多的带正电的粒子，并且它可以解释实验中观察到的粒子的快速凝固生长。提出了一种测量粒子光剥离截面的实验方法。带负电荷的粒子将在脉冲等离子体中生长，从脉冲等离子体中提取，并通过紫外线光分离室发送。准分子灯将用于在宽波长范围内产生窄带紫外线辐射。静电分析仪将用于测定经历光剥离的颗粒的比例。该结果可能导致对半导体等离子体中粒子生长的理解，并可能显示一种避免“杀伤粒子”凝固生长的方法。教育计划的重点是提高人们对等离子体加工和纳米粒子研究领域的认识，并传递这种兴奋。高中学生将通过简短的讲座和实验室参观获得研究的第一手印象。高中教师将被邀请参加暑期研究活动，并被建议开发令人兴奋的“尘埃等离子体”相关的课堂实验。本科学生将通过课程开发和交互式计算机教学材料的开发来解决问题。学生将体验研究的兴奋，通过研究级等离子体模拟代码在“虚拟等离子体”上工作，并有机会在实验室演示中将他们的结果与“真实”等离子体进行比较。他们还将有机会通过研究助理奖学金和荣誉论文项目直接参与研究。研究生将受益于该计划，特别是通过国际交流的机会。