Excimer Laser System for Pump-Probe Experiments

用于泵浦探测实验的准分子激光系统

• 批准号: 9212389
• 负责人: John Miller
• 金额: $ 6.53万
• 依托单位: George Washington University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-08-01 至 1994-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9212389&HistoricalAwards=false
• 关键词: Excimer; Laser; System; Pump; Probe

An Excimer Laser System will be purchased and used to support several established research programs in combustion chemistry, materials processing , and chemical analysis at George Washington University. These programs include laser-solid interaction in synthetic diamond film formation, laser sampling of glass and ceramic targets for chemical analysis, laser production of radical species important in combustion processes, and photodissociation of chlorinated hydrocarbons. In the first two areas, the goal will be to follow changes occurring on the surface and within the bulk of the targets and to examine the properties of the generated plumes. Methods of investigation will include time-of-flight mass spectrometry, kinetic energy measurement of the ions produced, and analysis of particulates in the plumes. In addition, laser-solid interactions will be examined theoretically for a broad range of lasers and selected materials. In the third area, excimer laser photolysis will be used to prepare radical species which are important in combustion systems. Absorption spectra for these species will then be obtained using an existing tunable diode laser spectrometer. Use of excimer laser photolysis followed by IR absorption as a diagnostic for chlorinated hydrocarbons in lab scale diffusion flames will also be explored. The general objectives of the first two activities are to enhance the understanding of laser-solid interactions and to use this knowledge in preparative and analytical applications. This will include optimization of laser sampling and pulsed laser deposition processes. In addition, a better understanding of synthetic diamond formation is a goal. In the latter activities, excimer laser photolysis has become the technique of choice for the preparation of a number of gas phase radical species for fundamental spectroscopic studies. Additionally, it is proposed that excimer laser photolysis of chlorinated hydrocarbons might also be used for the detection of undesirable combustion products.

将购买准分子激光系统并用于支持乔治华盛顿大学在燃烧化学、材料加工和化学分析方面的几个已建立的研究项目。 这些项目包括合成金刚石薄膜形成中的激光-固体相互作用、用于化学分析的玻璃和陶瓷靶材的激光采样、燃烧过程中重要的自由基物质的激光产生以及氯化烃的光解。 在前两个领域，目标将是跟踪目标表面和主体内部发生的变化，并检查生成的羽流的特性。 研究方法包括飞行时间质谱分析、产生的离子的动能测量以及羽流中的颗粒分析。 此外，将从理论上检查各种激光器和选定材料的激光-固体相互作用。 在第三个领域，准分子激光光解将用于制备燃烧系统中重要的自由基物质。 然后使用现有的可调谐二极管激光光谱仪获得这些物质的吸收光谱。 还将探索使用准分子激光光解和红外吸收作为实验室规模扩散火焰中氯化烃的诊断。 前两项活动的总体目标是增强对激光-固体相互作用的理解，并将这些知识用于制备和分析应用。 这将包括激光采样和脉冲激光沉积工艺的优化。 此外，我们的目标是更好地了解人造金刚石的形成。 在后面的活动中，准分子激光光解已成为制备用于基础光谱研究的多种气相自由基物质的首选技术。 此外，有人提出，氯化烃的准分子激光光解也可用于检测不需要的燃烧产物。