Understanding the Influence of Low-Frequency Vibrations on Energy Relaxation Through Layered Nanomaterials

通过层状纳米材料了解低频振动对能量弛豫的影响

基本信息

批准号：
1807999
负责人：
Kenneth Knappenberger
金额：
$ 37.57万
依托单位：
Pennsylvania State Univ University Park
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-08-01 至 2023-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1807999&HistoricalAwards=false
关键词：
Understanding Influence Low Frequency Vibrations

项目摘要

Quantum-confinement occurs when an object's dimensions are small compared to the size of electron motion. Many modern electronic devices, which range from medical diagnostics and therapeutics instruments, to high-resolution optical displays and flexible electronics, rely on quantum-confined nanostructures. However, realization of their full potential requires a fundamental understanding of their interactions with light. With support from the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry, Professor Kenneth Knappenberger from Pennsylvania State University (PSU) is developing advanced magneto-optical measurement capabilities to probe quantum-confined structures. Professor Knappenberger and his students are using the unique capabilities of this instrument to understand the behavior of electrons in transition metal dicholcogenide (TMD) materials, and how they interact with vibrations in the crystal lattice. The insights gained from the work could impact existing optoelectronic and photonic technologies, as well as emerging quantum information and sensing applications. The project is also providing training opportunities for future scientists in advanced experimental techniques. As part of this project, Professor Knappenberger has established a local student section of the Optical Society of America at Penn State. This activity facilitates a weekly brown-bag optics club lunch, hosted in the Millennium Science Complex at PSU. Students are able to present their research progress in an informal setting that includes faculty, postdoctoral, graduate, and undergraduate students. The program also includes a component for a high school volunteer student. This student acquires skills in data analysis and processing. The research team is developing and using novel variable-temperature, variable-magnetic field (VTVH) spectroscopy methods to characterize the electronic structure of a series of two-dimensionally confined quantum materials, including multi-component structures featuring combinations of 0-D/1-D/2-D systems. The overall objective is to understand how electronic carrier coupling to low-frequency phonon modes affects the relaxation dynamics of these systems. In order to achieve this fundamental research goal, the team is developing VTVH ultrafast two-dimensional spectroscopy (VTVH-2DES) capabilities, and using them to characterize key parameters of transient exciton states, such as Lande g factors, zero-field splitting energies, and electron-phonon coupling strengths. Monitoring transient signal amplitudes from these excitons in the time- and energy-domains provides insight into phonon-mediated energy relaxation and transfer in quantum materials. The research activities include 1) understanding the optical properties and electronic structure for single and multi-layer 2-D confined TMDs, 2) development of VTVH-2DES infrastructure of characterizing TMD transient states, 3) quantitatively describing quantum-state-specific electron-phonon coupling and carrier dynamics for TMDs; and 4) understanding fundamental mechanisms of phonon-mediated energy transfer in multi-component quantum structures.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.

当物体的尺寸与电子运动的尺寸相比较小时，就会发生量子限制。许多现代电子设备，从医疗诊断和治疗仪器到高分辨率光学显示器和柔性电子产品，都依赖于量子限制纳米结构。然而，要充分发挥它们的潜力，需要对它们与光的相互作用有基本的了解。在化学系高分子、超分子和纳米化学项目的支持下，宾夕法尼亚州立大学 (PSU) 的 Kenneth Knappenberger 教授正在开发先进的磁光测量能力来探测量子限制结构。 Knappenberger 教授和他的学生正在利用该仪器的独特功能来了解过渡金属二酰基化物 (TMD) 材料中电子的行为，以及它们如何与晶格中的振动相互作用。从这项工作中获得的见解可能会影响现有的光电和光子技术，以及新兴的量子信息和传感应用。该项目还为未来的科学家提供先进实验技术的培训机会。作为该项目的一部分，纳彭伯格教授在宾夕法尼亚州立大学建立了美国光学学会的当地学生分会。这项活动为每周一次的棕色袋光学俱乐部午餐提供了便利，该午餐在 PSU 的千年科学中心举办。学生能够在非正式的环境中展示他们的研究进展，其中包括教师、博士后、研究生和本科生。该计划还包括针对高中志愿者学生的组成部分。该学生获得数据分析和处理的技能。研究团队正在开发并使用新型变温变磁场（VTVH）光谱方法来表征一系列二维受限量子材料的电子结构，包括具有0-D/1组合的多组分结构-D/2-D 系统。总体目标是了解电子载波与低频声子模式的耦合如何影响这些系统的弛豫动力学。为了实现这一基础研究目标，该团队正在开发VTVH超快二维光谱（VTVH-2DES）能力，并利用它们来表征瞬态激子态的关键参数，例如Lande g因子、零场分裂能、和电子声子耦合强度。在时域和能量域中监测这些激子的瞬态信号幅度可以深入了解量子材料中声子介导的能量弛豫和转移。研究活动包括 1) 了解单层和多层二维受限 TMD 的光学特性和电子结构，2) 开发表征 TMD 瞬态的 VTVH-2DES 基础设施，3) 定量描述量子态特定电子TMD 的声子耦合和载流子动力学； 4) 了解多组分量子结构中声子介导的能量转移的基本机制。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力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

期刊论文数量（16）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Unexpected Near-Infrared to Visible Nonlinear Optical Properties from 2-D Polar Metals

二维极性金属具有意想不到的近红外到可见非线性光学特性

DOI：
10.1021/acs.nanolett.0c03481
发表时间：
2020-01
期刊：
Nano Letters
影响因子：
10.8
作者：
Steves, Megan A.;Wang, Yuanxi;Briggs, Natalie;Zhao, Tian;El;Bersch, Brian M.;Subramanian, Shruti;Dong, Chengye;Bowen, Timothy;Fuente Duran, Ana De;et al
通讯作者：
et al

Achieving sub-diffraction spatial resolution using combined Fourier transform spectroscopy and nonlinear optical microscopy

使用组合傅里叶变换光谱和非线性光学显微镜实现亚衍射空间分辨率