Coherent Phase Control in Isolated Molecules and Condensed Phases

孤立分子和凝聚相的相干相位控制

• 批准号: 0200812
• 负责人: Robert Gordon
• 金额: $ 51.07万
• 依托单位: University of Illinois at Chicago
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-05-01 至 2006-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0200812&HistoricalAwards=false
• 关键词: Coherent; Phase; Control; Isolated; Molecules

This research investigates the application of the phase of laser light to understand and manipulate the behavior of electrons and/or nuclei in isolated molecules and in condensed matter. By varying the relative phase of two electromagnetic fields, it is possible to control the interference between two competing excitation paths and thereby to alter the branching ratio of a chemical reaction or the direction of a photocurrent. Moreover, from the laser-phase dependence of the observable, it is possible to obtain fundamentally new information about continuum structure. Three new initiatives are designed to deepen our understanding of such interference effects. The first is the application of coherent control to bond-selective chemistry of complex molecules. Specifically, the interference between one- and three-photon excitation will be used to control the product distribution in the photodissociation of vinyl chloride. Second, coherent control will be used to manipulate the photodissociation of hydrogen molecules in selected vibrational and rotational levels. The phase lag spectrum for this process will then be compared with theoretical predictions. Finally, the theory of phase-lag spectroscopy will be extended to deal with surface resonances, thereby providing a tool for understanding a variety of decay and decoherence mechanisms relevant to photon- and electron-triggered surface chemistry and to electron transport in molecular devices. This project is jointly funded by the AMOP program in the Physics Division and the EPC program in the Chemistry Division.

本研究探讨了激光相位的应用，以理解和操纵孤立分子和凝聚态物质中电子和/或原子核的行为。通过改变两个电磁场的相对相位，可以控制两个竞争激发路径之间的干扰，从而改变化学反应的分支比或光电流的方向。此外，从激光相位依赖的可观察性，它是可能的，以获得新的信息，从根本上连续结构。三项新举措旨在加深我们对这种干扰影响的理解。第一个是相干控制在复杂分子选键化学中的应用。具体而言，一个和三个光子激发之间的干扰将被用来控制在氯乙烯的光解产物分布。第二，相干控制将被用来操纵选定的振动和转动水平的氢分子的光解。然后将这个过程的相位滞后谱与理论预测进行比较。最后，相位滞后光谱的理论将被扩展到处理表面共振，从而提供了一种工具，用于理解各种衰减和退相干机制相关的光子和电子触发的表面化学和电子传输的分子器件。 该项目由物理系的AMOP计划和化学系的EPC计划共同资助。