Measuring Electronic Coherence at the Single-Molecule Level with Nonlinear Coherent Spectroscopy

使用非线性相干光谱测量单分子水平的电子相干性

• 批准号: 2106799
• 负责人: Elad Harel
• 金额: $ 47.62万
• 依托单位: Michigan State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2106799&HistoricalAwards=false
• 关键词: Measuring; Electronic; Coherence; Single; Molecule

With support from the Chemical Measurement and Imaging (CMI) Program in the Division of Chemistry, Dr. Elad Harel and his research group at Michigan State University are developing new methods to measure the quantum mechanical behavior of single molecules. In quantum mechanics, the behavior of a molecule often depends on a delicate relationship between the different states of the system. This relationship, called coherence, is easily disrupted through interactions with the surrounding environment, and often requires experimentalists to make difficult measurements at low temperatures or in highly isolated environments in order to probe the quantum mechanical properties of a complex system. However, it is becoming increasingly clear that even under ambient conditions quantum mechanics plays an important role in the behavior of molecular systems, including photosynthetic proteins that convert sunlight into chemical energy. While coherence has been measured for collections of molecules, knowing the behavior of single molecules is important for understanding how molecular structure affects the function of complex systems. Therefore, Professor Harel’s team is developing tools to measure coherence at the single-molecule level by employing extremely sensitive detection methods. The research project also provides advanced technical training for students, as well as outreach activities targeting a wide audience of young people from a range of economic and social backgrounds.The development of nonlinear spectroscopy methods at the single-molecule level holds the promise of revealing important information that is not currently available from ensemble methods. In this project, Dr. Harel and his group are developing new methods to enable single-molecule nonlinear spectroscopy measurements at room temperature. The approach uses two-dimensional electronic spectroscopy to probe electronic coherences and electronic-vibrational coupling at the single-molecule level. These measurements reveal important structure-function-dynamics relationships in complex systems, including pigment-protein complexes and quantum-confined nanocrystals under ambient conditions. Understanding the true electronic coherence time and its physical origin free of inhomogeneous broadening are critically important for comparing experimental measurements with theoretical predictions, and for developing a deeper fundamental understanding of molecular interactions. The new approach being developed by the research team has the potential to impact understanding of molecular mechanisms that govern a wide range of complex chemical systems. In addition to enabling important new measurements of molecular systems, the research goals of the project are closely integrated with student training at the graduate and undergraduate levels, including a program in which graduate students develop five-week summer tutorial courses based on their research.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在化学系化学测量和成像 (CMI) 项目的支持下，密歇根州立大学的 Elad Harel 博士和他的研究小组正在开发测量单分子量子力学行为的新方法。分子的状态通常取决于系统不同状态之间的微妙关系，这种关系称为相干性，很容易通过与周围环境的相互作用而被破坏，并且通常需要实验人员在低温或高度隔离的环境中进行困难的测量。为了探查然而，越来越清楚的是，即使在环境条件下，量子力学也在分子系统的行为中发挥着重要作用，包括将阳光转化为化学能的光合蛋白质，同时对集合的相干性进行了测量。因此，Harel 教授的团队正在开发通过采用极其灵敏的检测方法来测量单分子水平的相干性的工具。还提供高级技术培训为学生，以及针对来自不同经济和社会背景的广大年轻人的外展活动。单分子水平非线性光谱方法的发展有望揭示目前无法从整体中获得的重要信息在该项目中，Harel 博士和他的团队正在开发新方法，以实现室温下的单分子非线性光谱测量，该方法使用二维电子光谱来探测单分子的电子相干性和电子振动耦合。水平.这些测量揭示了复杂系统中重要的结构-功能-动力学关系，包括环境条件下的色素-蛋白质复合物和量子限制纳米晶体，了解真实的电子相干时间及其无不均匀展宽的物理起源对于将实验测量与理论进行比较至关重要。研究团队开发的新方法除了能够实现重要的新分子测量之外，还有可能影响对控制广泛复杂化学系统的分子机制的理解。系统，该项目的研究目标与研究生和本科生的学生培训紧密结合，其中包括研究生根据其研究开发为期五周的夏季辅导课程的计划。该奖项反映了 NSF 的法定使命，并被认为是值得的通过使用基金会的智力优势和更广泛的影响审查标准进行评估来提供支持。