Studies of the Control of Quantum Dynamics

量子动力学控制研究

• 批准号: 9807127
• 负责人: Stuart Rice
• 金额: $ 43.68万
• 依托单位: University of Chicago
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-01 至 2002-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9807127&HistoricalAwards=false
• 关键词: Studies; Control; Quantum; Dynamics

Stuart Rice is supported by a grant from the Theoretical and Computational Chemistry Program to continue his work on the theory of control of the evolution of quantum many body systems with applications to the selective enhancement of products of a chemical reaction. Four areas of study will be pursued: 1) refinements and extensions of the Kobrak-Rice photoselective adiabatic passage scheme; 2) the accuracy of reduced dynamical descriptions of an excited molecule; 3) the control of the evolution of a molecule embedded in a solvent; and 4) the possible existence of a fundamental limit to the extent of control of quantum dynamics that is attainable. Much of the theoretical approach to coherent control will be developed as an extension to the generalized Stimulated Raman Adiabatic Passage (StiRAP) process for control of product selectivity in a reaction.The achievement of selective control of product formation in a reaction has been sought persistently throughout the evolution of chemistry. To date, such control has only been accomplished at the macroscopic level, by the manipulation of external factors such as temperature, pressure, solvent character, etc. With the advent of the tunable laser, it was hoped that product selectivity could be controlled at the microscopic level, and that individual bonds within a molecule could be selectively broken. It was very quickly found that energy absorbed by a molecule was not easily localized in individual bonds, but preferred to redistribute throughout the molecule. More recently, however, the concept of laser selective chemistry has had a rebirth, and theories developed by Rice and others have shown that energy could be localized by carefully choosing a complex sequence of laser pulses of prescribed shapes. If this theory can be put to practice experimentally, it may still be possible to realize the goal of microscopic selective control of chemical reactions.

斯图尔特·赖斯得到了理论和计算化学计划的资助，继续他在量子多体系统进化控制理论方面的工作，并应用于化学反应产物的选择性增强。 研究的四个领域将继续进行：1）的Kobrak-Rice光选择性绝热通过方案的改进和扩展; 2）减少动力学描述的激发分子的准确性; 3）嵌入在溶剂中的分子的演化控制;和4）可能存在的基本限制的程度控制的量子动力学是可以实现的。 相干控制的许多理论方法将作为广义受激拉曼绝热通道（StiRAP）过程的扩展来发展，用于控制反应中产物的选择性。到目前为止，这种控制只完成了在宏观层面上，通过操纵外部因素，如温度，压力，溶剂特性等，随着可调谐激光器的出现，人们希望，产品的选择性可以在微观层面上控制，并在一个分子内的各个键可以选择性地打破。人们很快发现，分子吸收的能量不容易局限在单个键中，而是倾向于在整个分子中重新分布。然而，最近，激光选择性化学的概念已经重生，赖斯和其他人发展的理论表明，通过仔细选择具有规定形状的激光脉冲的复杂序列，能量可以被局部化。如果这一理论能够在实验上得到应用，那么实现化学反应的微观选择性控制的目标还是有可能的。