CAREER: Photodetachment from Nanometer-Sized Particles

该项目致力于研究纳米颗粒的基本性质，并测量目前尚未探索的性质，如光分离和光电离。结果表明，由于紫外光辐射引起的电子光剥离是一种重要的、迄今被忽略的效应，它可以导致更多带正电荷的粒子，并解释了实验观察到的粒子的快速凝聚生长。提出了一种测量颗粒光剥离截面的实验方法。带负电荷的粒子将在其中生长，从脉冲等离子体中提取，并通过紫外光分离室发送。准分子灯将被用来在宽波长范围内产生窄带紫外线辐射。静电分析仪将被用来确定经历了光分离的颗粒的比例。这些结果可能有助于理解半导体等离子体中粒子的生长，并可能展示一种避免“杀手级粒子”凝聚生长的方法。该教育计划的重点是提高人们对等离子体处理和纳米粒子研究领域的认识并传递兴奋情绪。高中生将通过简短的讲座和参观实验室获得研究的第一手印象。高中教师将被邀请参加暑期的研究活动，并被建议开发令人兴奋的“尘埃等离子体”相关课堂实验。本科生将通过课程开发和交互式、基于计算机的教材开发来解决问题。学生将通过使用研究级别的等离子体模拟代码来体验研究的兴奋，并有机会将他们的结果与实验室演示中的“真实”等离子体进行比较。他们还将有机会通过研究助学金和荣誉论文项目直接参与研究。研究生将从该项目中受益，特别是通过国际交流的机会。

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.