Elucidation of Hot-Electron Transport and Exploitation of Hot-Carrier Plasmonics via Nonlinear Optical Effects

通过非线性光学效应阐明热电子传输和热载流子等离子体的开发

• 批准号: 2004749
• 负责人: Wenshan Cai
• 金额: $ 39.8万
• 依托单位: Georgia Tech Research Corporation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2004749&HistoricalAwards=false
• 关键词: Elucidation; Hot; Electron; Transport; Exploitation

The behavior of energetic electrons, termed “hot” electrons, is essential for applications in chemical synthesis, energy harvesting, and information technology. Further advances of this area of research demand deepened knowledge of the behavior of such charged electrons after excitation with light. This excitation process is a complicated phenomenon consisting of a number of sequential processes, most of which happen within one billionth of a second. This research team controls the behavior of these hot electrons with other optical effects to understand the generation, transport, and decay of electrons. Moreover, the ultrafast behavior of optically induced hot electrons is harnessed for the all-optical control of light. The knowledge gained through this project lays the groundwork at the interface of semiconductors and optics, and leads to new insights into the design and implementation of devices for the detection and processing of light. This research, included with high school and collegiate education, promotes multidisciplinary thinking of the up-and-coming scientists and engineers. The project broadly disseminates interdisciplinary knowledge derived from this research effort, encourages early engagement of the youth via integration of research and education, and enhances the learning opportunities for high school students from minority groups.The dynamics of plasmonically induced hot carriers is pivotal to a wide range of photophysical and photochemical processes. The current understanding is partially constrained by the capacities of prevailing characterization methods. Moreover, the fundamentals and applications of hot-carrier plasmonics are predominantly focused on the linear optical regime, while rather limited work has investigated the involvement of hot carriers in nonlinear light-matter interactions. This project aims to elucidate the dynamics of the generation, transfer, and thermalization of hot carriers via nonlinear optical means, and furthermore, to exploit hot-carrier induced nonlinear optical processes for signal detection and processing in photonic and quantum systems. The overall content of this research is to establish a new technique for the investigation and utilization of the ultrafast dynamics of hot carriers based on the second- and third-order nonlinear optical effects. Such novel nonlinear processes are explored in hybrid plasmonic platforms, where nanostructured metals interface electron-accepting materials. Of particular interest are the implementations of two hot-carrier induced phenomena, namely, the transient optical Kerr nonlinearity and the transient second-harmonic generation, for the investigation of hot-electron dynamics and the realization of ultrafast all-optical control of light. The successful execution of the research leads to new understanding of light-matter interactions at reduced dimensions, and facilitates improved understanding of hot-carrier physics, optical signal processing, and quantum transport.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.

高能电子的行为，被称为“热”电子，在化学合成、能量收集和信息技术的应用中是必不可少的。这一研究领域的进一步发展需要深入了解这些带电电子在光激发后的行为。这个激发过程是一个复杂的现象，由许多连续的过程组成，其中大多数发生在十亿分之一秒内。该研究小组通过其他光学效应控制这些热电子的行为，以了解电子的产生、传输和衰变。此外，光诱导热电子的超快行为被利用于光的全光控制。通过该项目获得的知识为半导体和光学的接口奠定了基础，并为光的检测和处理设备的设计和实现带来了新的见解。这项研究，包括高中和大学教育，促进有前途的科学家和工程师的多学科思维。该项目广泛传播从这项研究工作中获得的跨学科知识，通过研究和教育的结合鼓励青年早期参与，并增加少数民族高中生的学习机会。等离子体诱导热载流子的动力学是广泛的光物理和光化学过程的关键。目前的理解部分受到流行表征方法能力的限制。此外，热载子等离子体的基础和应用主要集中在线性光学领域，而研究热载子在非线性光-物质相互作用中的作用的工作相当有限。本项目旨在通过非线性光学手段阐明热载流子的产生、传递和热化的动力学，并进一步利用热载流子诱导的非线性光学过程用于光子和量子系统中的信号检测和处理。本研究的总体内容是建立一种基于二阶和三阶非线性光学效应的热载流子超快动力学研究和利用的新技术。这种新颖的非线性过程在混合等离子体平台上进行了探索，其中纳米结构金属与电子接受材料界面。特别感兴趣的是两种热载子诱导现象的实现，即瞬态光学克尔非线性和瞬态二次谐波的产生，用于研究热电子动力学和实现超快全光控制。该研究的成功实施导致了对降维光物质相互作用的新理解，并促进了对热载流子物理、光信号处理和量子输运的更好理解。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Photonic upconversion maximization for nonlinear meta-material enabled by deep learning

通过深度学习实现非线性超材料的光子上转换最大化

• DOI: 10.1117/12.2651695
• 发表时间: 2023
• 期刊: SPIE
• 作者: Raju, Lakshmi;Liu, Zhaocheng;Zhu, Dayu;Kim, Andrew;Poutrina, Ekaterina;Urbas, Augustine;Cai, Wenshan
• 通讯作者: Cai, Wenshan

Polarimetric analysis of thermal emission from both reciprocal and nonreciprocal materials using fluctuation electrodynamics

• DOI: 10.1103/physrevb.106.245407
• 发表时间: 2022-09
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Chiyu Yang;W. Cai;Zhuomin M. Zhang

Maximized Frequency Doubling through the Inverse Design of Nonlinear Metamaterials

• DOI: 10.1021/acsnano.1c09298
• 发表时间: 2022-03-22
• 期刊: ACS NANO
• 影响因子: 17.1
• 作者: Raju, Lakshmi;Lee, Kyu-Tae;Cai, Wenshan
• 通讯作者: Cai, Wenshan

Enantiomer‐Selective Molecular Sensing in the Nonlinear Optical Regime via Upconverting Chiral Metamaterials

• DOI: 10.1002/adfm.202208641
• 发表时间: 2022-08
• 期刊: Advanced Functional Materials
• 影响因子: 19
• 作者: Kyu-Tae Lee;B. Kim;L. Raju;S. Rodrigues;Doo‐Hyun Ko;W. Cai