CAREER: Molecular polaritonics: new opportunities for spectroscopy and control of charge and energy transport

职业：分子极化子学：光谱学以及电荷和能量传输控制的新机遇

• 批准号: 1654732
• 负责人: Joel Yuen-Zhou
• 金额: $ 65.7万
• 依托单位: University of California-San Diego
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-02-01 至 2025-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1654732&HistoricalAwards=false
• 关键词: CAREER; Molecular; polaritonics; new; opportunities

Joel Yuen-Zhou, of the University of California San Diego (UCSD), is supported by an award from the Chemical Theory, Models and Computational Methods program in the Division of Chemistry and the Condensed Matter and Materials Theory program in the Division of Materials Research to develop theoretical and computational methods to study hybrid quantum mechanical states of light (photons) interacting excited molecular states (excitons). These light-matter hybrid states, known as polaritons, have emergent properties that do not exist in the separate components alone. This research harnesses the duality of polaritons to design ways in which light-matter interactions may be exploited to obtain novel ways to manipulate transport of charge and light-harvested energy. Typically, energy captured from sunlight moves across a molecular antenna in the form of excitons, neutral nanoscale excitations transported across molecules. Understanding and controlling exciton transport in molecular materials is a significant challenge for the theory of condensed phases physics and chemistry, as well as a primary concern for studies of photosynthesis and new light-harvesting technologies, such as organic solar cells. This project trains graduate students and postdoctoral fellows to be conversant on research at the intersection of theoretical chemistry, nano-photonics, and condensed matter theory. It also develops a broad outreach plan to school students via a series of performance choreographies mimicking collective phenomena in topological materials. Dr. Yuen-Zhou is also involved in developing a new orientation strategy to accommodate the increasing international graduate student population in his department at UCSD.Polaritons inherit wavelike properties from light such as extended spatial coherence, but also matter properties which allow energy to localize energy and give rise to a chemical reaction or to strong interactions between charged particles. This research harnesses the duality of polaritons to design ways in which light-matter interaction interact to produce phenomena that do not occur via each of the components alone. An example of this is enhanced charge transport or topologically-protected energy transport in the nano- and mesoscales. Here, topological refers to properties that do not require fine-tuning of parameters to survive, but rather, rely on global characteristics which are robust to material imperfections and impurities. This investigation focuses on the unusually delocalized exciton states of molecular polaritons. By noting that dipolar light-matter interaction is anisotropic and isomorphic to spin-orbit coupling, the research harnesses the latter to induce exotic polaritonic effects akin to those found in topological insulators, giving rise to spatial and directional control of nano- and mesoscale energy flow which is robust to disorder. These ideas are first tested on purely excitonic systems of porphyrin arrays and then on similar systems of chromophores in confined electromagnetic environments. Analogies to Dirac systems in two-dimensional materials such as graphene prove fruitful and give rise to unexplored frontiers of molecular aggregates. The Yuen-Zhou group also addresses recent observations suggesting that confined electromagnetic fields can enhance the conductivity of organic polymers owing to the formation of delocalized polaritons, opening new avenues for control of electron transport in molecular materials. Even though the project is theoretical in nature, it has a strong spectroscopic component aimed at simulating measurements that experimentalists might produce. Collaborations with experimentalists are a strong component of the work. Yuen-Zhou and coworkers are providing the first theoretical and computational framework to describe the interplay between topological band structures and vibronic degrees of freedom, including the deleterious or beneficial effects of vibrational decoherence. They are also studying a comprehensive theory for polaritons-assisted charge transport. These studies provide insights on the limits of controllability of energy and charge flow in the nano- and mesoscales, as well as new paradigms for the design light-harvesting technologies and optical logic devices. The development of the scientific component is accompanied by the training of graduate students and postdoctoral fellows in an interdisciplinary environment. Upon completion of their work, trainees are prepared to face a wide variety of contemporary scientific challenges, both in academic and industrial settings. The project also includes a multifaceted educational project with the goal of popularizing abstract concepts of topological phases of matter to a broad audience. This consists of a series of experiential and interpretative dance events termed Top-Dances, where high-school students participate in collective choreographies that aim to recreate energy and charge transport in quasi-two-dimensional materials such as those addressed in the project. These events are recorded, analyzed, digested in the events, and distributed in social media to provide alternative and intuitive ways to visualize the aforementioned concepts. Finally, as a response to the recent rise of international graduate students in the Department of Chemistry and Biochemistry of UCSD, Professor Yuen-Zhou also redesigns an orientation program with the goal of fostering a more effective integration of these students into a challenging academic and research environment. This goal is carried out through a series of workshops addressing issues of academic leadership and diversity, as well as the installation of a mentoring support network within the department.

加州圣地亚哥大学（UCSD）的Joel Yuen-Zhou获得了化学系化学理论、模型和计算方法项目以及材料研究系凝聚态和材料理论项目的奖项，以开发理论和计算方法来研究光（光子）相互作用的激发分子态（激子）的混合量子力学状态。 这些光-物质混合态，被称为极化激元，具有单独存在于单独成分中不存在的涌现特性。这项研究利用极化激元的双重性来设计方法，在这些方法中，可以利用光-物质相互作用来获得操纵电荷和光收集能量的传输的新方法。通常，从阳光中捕获的能量以激子的形式穿过分子天线，中性纳米级激发穿过分子。理解和控制分子材料中的激子输运是凝聚相物理和化学理论的重大挑战，也是光合作用和新的光捕获技术（如有机太阳能电池）研究的主要关注点。该项目培养研究生和博士后研究员熟悉理论化学，纳米光子学和凝聚态理论的交叉研究。它还通过一系列模仿拓扑材料中集体现象的表演编排，为学校学生制定了广泛的推广计划。Yuen-Zhou博士还参与开发一种新的定向策略，以适应加州大学圣地亚哥分校他所在的部门不断增加的国际研究生人口。极化激元继承了光的类波特性，如扩展的空间相干性，但也具有物质特性，允许能量局部化能量，并引起化学反应或带电粒子之间的强烈相互作用。这项研究利用极化激元的二元性来设计光-物质相互作用的方式，以产生不会单独通过每个组件发生的现象。 这方面的一个例子是增强的电荷传输或拓扑保护的能量传输在纳米和中尺度。这里，拓扑是指不需要微调参数就能生存的属性，而是依赖于对材料缺陷和杂质具有鲁棒性的全局特性。本研究的重点是分子极化激元的非定域激子态。通过注意到偶极光-物质相互作用是各向异性的，并且与自旋-轨道耦合同构，该研究利用后者来诱导与拓扑绝缘体中发现的那些类似的奇异极化激元效应，从而引起对纳米和中尺度能量流的空间和方向控制，这对无序是鲁棒的。这些想法首先测试纯激子系统的卟啉阵列，然后在封闭的电磁环境中的发色团的类似系统。在二维材料如石墨烯中与狄拉克系统的类比证明是富有成效的，并引起了分子聚集体的未探索的前沿。Yuen-Zhou小组还讨论了最近的观察结果，这些观察结果表明，由于离域极化激元的形成，受限电磁场可以增强有机聚合物的导电性，为控制分子材料中的电子传输开辟了新的途径。尽管该项目本质上是理论性的，但它具有强大的光谱成分，旨在模拟实验学家可能产生的测量结果。与实验者的合作是这项工作的重要组成部分。 Yuen-Zhou及其同事提供了第一个理论和计算框架来描述拓扑能带结构和振动自由度之间的相互作用，包括振动退相干的有害或有益影响。 他们还在研究极化激元辅助电荷传输的综合理论。这些研究提供了对纳米和中尺度能量和电荷流可控性限制的见解，以及设计光捕获技术和光学逻辑器件的新范例。科学部分的发展是伴随着研究生和博士后研究员在跨学科环境中的培训。在完成他们的工作后，学员准备面对各种各样的当代科学挑战，无论是在学术和工业环境。该项目还包括一个多方面的教育项目，目的是向广大受众普及物质拓扑相的抽象概念。这包括一系列名为Top-Dances的体验性和解释性舞蹈活动，高中生参加集体编舞，旨在在准二维材料中重现能量和电荷传输，例如该项目中提到的那些。这些事件被记录，分析，消化在事件中，并在社交媒体中分发，以提供替代和直观的方式来可视化上述概念。最后，为了应对加州大学圣地亚哥分校化学与生物化学系最近国际研究生人数的增加，Yuen-Zhou教授还重新设计了一个定向计划，旨在促进这些学生更有效地融入具有挑战性的学术和研究环境。这一目标是通过一系列研讨会解决学术领导力和多样性的问题，以及在部门内安装一个辅导支持网络。

项目成果

Two-dimensional infrared spectroscopy of vibrational polaritons

• DOI: 10.1073/pnas.1722063115
• 发表时间: 2018-05-08
• 期刊: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• 影响因子: 11.1
• 作者: Xiang, Bo;Ribeiro, Raphael F.;Xiong, Wei
• 通讯作者: Xiong, Wei

Theory for Nonlinear Spectroscopy of Vibrational Polaritons

• DOI: 10.1021/acs.jpclett.8b01176
• 发表时间: 2018-07-05
• 期刊: JOURNAL OF PHYSICAL CHEMISTRY LETTERS
• 影响因子: 5.7
• 作者: Ribeiro, Raphael F.;Dunkelberger, Adam D.;Yuen-Zhou, Joel
• 通讯作者: Yuen-Zhou, Joel

Manipulating optical nonlinearities of molecular polaritons by delocalization

• DOI: 10.1126/sciadv.aax5196
• 发表时间: 2019-09-01
• 期刊: SCIENCE ADVANCES
• 影响因子: 13.6
• 作者: Xiang, Bo;Ribeiro, Raphael F.;Xiong, Wei
• 通讯作者: Xiong, Wei

Comment on ‘Quantum theory of collective strong coupling of molecular vibrations with a microcavity mode’

评《分子振动与微腔模式集体强耦合的量子理论》

• DOI: 10.1088/1367-2630/aaa751
• 发表时间: 2018
• 期刊: New Journal of Physics
• 影响因子: 3.3
• 作者: Martínez-Martínez, Luis A;Yuen-Zhou, Joel
• 通讯作者: Yuen-Zhou, Joel

Vibronic Ground-State Degeneracies and the Berry Phase: A Continuous Symmetry Perspective

电子振动基态简并和浆果相：连续对称视角

• DOI: 10.1021/acs.jpclett.7b02592
• 发表时间: 2017
• 期刊: The Journal of Physical Chemistry Letters
• 作者: Ribeiro, Raphael F.;Yuen-Zhou, Joel
• 通讯作者: Yuen-Zhou, Joel