Studying Correlated Electron Dynamics in Molecules and Materials with Isolated Attosecond Pulses

用孤立阿秒脉冲研究分子和材料中的相关电子动力学

• 批准号: 1505556
• 负责人: Arvinder Sandhu
• 金额: $ 32.18万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1505556&HistoricalAwards=false
• 关键词: Studying; Correlated; Electron; Dynamics; Molecules

Electrons play a fundamental role in most natural and laboratory phenomena. These elementary particles are extremely light and agile--they can move inside atoms, molecules and materials on the timescale of "attoseconds," which is a billionth of a billionth of a second. To understand the functioning of physical, chemical, and biological processes, it is important to be able to resolve and control the underlying fast electronic motion. Newly devised attosecond techniques provides exactly such an opportunity, using light pulses to strobe the dynamics of electrons. However, most initial studies in this field have been conducted on simple systems like atoms and small molecules. The researchers supported by this program will develop and extend attosecond techniques to the study of complex molecules and materials, where one or more electrons are interacting with each other. Success along these directions will open up opportunities for direct investigation of many biochemical and nanomaterial processes relevant for light harvesting and energy storage. The proposed program will therefore advance the state of science by building bridges between the field of physics, and those of chemistry, biology, and material sciences. The project will also train the next generation of scientists belonging to diverse backgrounds in this emerging and interdisciplinary research field.Electronic correlation often dominates the excitation and relaxation dynamics of photo-excited molecules and nanomaterials, manifesting itself in the energy and charge redistribution mechanisms in important natural and laboratory processes, such as photosynthesis, repair and damage or DNA, energy storage at molecule-semiconductor interfaces etc. This research project aims at the investigation of correlation-driven physical and chemical phenomena using various types of ultrafast spectroscopy. The high temporal resolution required for these studies will be achieved through the generation of isolated attosecond pulses using double optical gating or similar schemes. The scientific objectives of this program will be to: (1) investigate coherent charge migration dynamics in polyatomic molecules, such as those consisting of a phenyl group, (2) study the coherence in electron wavepacket dynamics and the origin of decoherence mechanisms, and (3) probe the generation and dynamics of high energy excitons in carbon nanomaterials (e.g. graphene). These objectives will be achieved while training graduate and undergraduate students in the field of attosecond physics. Two powerful experimental techniques will be utilized in the proposed measurements: velocity map imaging and attosecond transient absorption. The investigations outlined in the proposal will provide the building blocks for developing a better understanding of the inner-workings of natural and practically relevant phenomena. Collaborations with theorists will play crucial role in the interpretation of results obtained in this unchartered territory, potentially leading to the development of new theoretical models.

电子在大多数天然和实验室现象中起着基本作用。 这些基本颗粒非常轻巧和敏捷 - 它们可以在“ attoseconds”时期内的原子，分子和材料内部移动，这是十亿分之一的十亿分之一。 要了解物理，化学和生物学过程的功能，能够解决和控制潜在的快速电子运动很重要。新设计的Attsond Techniques可以使用轻脉冲来刺激电子动力学。 但是，该领域的大多数初始研究都是在原子和小分子等简单系统上进行的。该程序支持的研究人员将开发并将其扩展到复杂分子和材料的研究，其中一个或多个电子之间正在相互作用。这些方向的成功将为直接调查与光收集和能源储存相关的许多生化和纳米材料过程提供直接调查的机会。因此，拟议的计划将通过在物理学领域以及化学，生物学和物质科学领域之间建立桥梁来推进科学状态。 The project will also train the next generation of scientists belonging to diverse backgrounds in this emerging and interdisciplinary research field.Electronic correlation often dominates the excitation and relaxation dynamics of photo-excited molecules and nanomaterials, manifesting itself in the energy and charge redistribution mechanisms in important natural and laboratory processes, such as photosynthesis, repair and damage or DNA, energy storage at该研究项目旨在使用各种类型的超快光谱法对相关驱动的物理和化学现象进行研究。这些研究所需的高时间分辨率将通过使用双光门控或类似方案产生分离的Attosond脉冲来实现。 The scientific objectives of this program will be to: (1) investigate coherent charge migration dynamics in polyatomic molecules, such as those consisting of a phenyl group, (2) study the coherence in electron wavepacket dynamics and the origin of decoherence mechanisms, and (3) probe the generation and dynamics of high energy excitons in carbon nanomaterials (e.g. graphene).这些目标将在培训Attosecond物理学领域的毕业生和本科生时实现。在提出的测量中将使用两种强大的实验技术：速度图成像和Attosend瞬时吸收。提案中概述的调查将为建立对自然和实际相关现象的内部工作的理解提供基础。与理论家的合作将在对这个未经特定领域获得的结果的解释中发挥至关重要的作用，这有可能导致新的理论模型的发展。