Probing and Controlling Electronic Dynamics in Matter with Atomic Spatiotemporal Resolution

用原子时空分辨率探测和控制物质中的电子动力学

• 批准号: 2110633
• 负责人: Uwe Thumm
• 金额: $ 27万
• 依托单位: Kansas State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-15 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2110633&HistoricalAwards=false
• 关键词: Probing; Controlling; Electronic; Dynamics; Matter

Photoelectron emission is a fundamental light-matter interaction process in nature. It occurs upon the incidence of electromagnetic radiation with sufficiently short wavelength and adequate intensity on matter, proceeds through the coupling of the incident radiation with electrons, and results in the transfer of photonic energy to internal excitations of the target and the emission of electrons. The emitted photoelectrons carry information about the photoemission dynamics and electronic properties of the target material. For more than a century, the measurement and analysis of their energy and momentum distribution has been one of the most prolific methods for determining the electronic structure of matter, importantly promoting the development of laser and detection technologies as well as accurate quantum-mechanical theoretical methods. Energy-domain spectra image the sample's time-averaged internal electronic dynamics during the photoemission process, but do not resolve the ultrafast time-dependent electronic dynamics during the photoelectron-release (or –rescattering) process. The proposed theoretical work is motivated by extraordinary progress in ultrafast laser technology that enabled the generation of ultrashort light pulses and their accurate control and synchronization. These pulses allow for investigations of the electronic dynamics in isolated atoms and condensed matter systems with temporal resolution at the natural timescale of the electronic motion in matter and with atomic spatial resolution. In the same way as making a movie of a fast-moving object, such as a bullet in flight, requires the stroboscopic assembly of many frames, each constituting a momentary image of the object, time-domain spectroscopy is about to provide “electronic movies”, capable of displaying the motion of electrons in and their emission from matter with atomic spatiotemporal resolution. The proposed studies will advance our understanding of (i) single--electron and collective electronic excitations and (ii) the dynamics of electrons and fields in layered semiconductors, adsorbate-covered surfaces, and nanoparticles, promoting emerging technologies, such as light-wave computing, nano-catalysis, and artificial photosynthesis, thereby contributing to the development of novel computers and catalytic devices for securing our energy supply and preserving our environment.Attosecond time-resolved spectroscopy has led to impressive time-domain studies of ionization processes on isolated (gaseous) atoms and is anticipated to significantly advance our understanding of electronic properties of layered-semiconductor structures and nanoparticles. However, the physical interpretation of time-resolved photoemission spectra faces significant conceptual challenges and necessitates comprehensive theoretical investigations, even for simple atomic systems. For complex systems, such as nanoparticles and solid surfaces, additional severe technical difficulties in describing the transiently photoexcited electronic dynamics must be overcome. The proposed work addresses these challenges. It focuses on the modeling of time- and spatially resolved emission of electrons and the generation of up-converted high-harmonic (HH) radiation from adsorbate-covered metal surfaces and nanoparticles. It proceeds by developing and applying complementary quantum-mechanical methods, including numerical solutions of the time-dependent Schrödinger equation, and physically more transparent semi-classical methods. It will assess the fidelity with which time- and emission-angle-resolved photoelectron and HH spectra can reveal information on (a) electronic forces and dynamics in solids and (b) non-homogenous nano-plasmonic electric-field enhancements of incident light pulses.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.

光电子发射本质上是一种基本的光-物质相互作用过程。它发生在具有足够短波长和足够强度的电磁辐射入射到物质上时，通过入射辐射与电子的耦合进行，并导致光子能量转移到目标的内部激发和电子的发射。发射的光电子携带有关目标材料的光电子发射动力学和电子性质的信息。一个多世纪以来，对其能量和动量分布的测量和分析一直是确定物质电子结构的最多产的方法之一，对激光和探测技术以及精确的量子力学理论方法的发展起着重要的推动作用。能域谱反映了样品在光电子发射过程中的时间平均内部电子动力学，但不能分辨光电子释放(或再散射)过程中的超快随时间变化的电子动力学。提出的理论工作的动机是超快激光技术的非凡进步，使超短光脉冲的产生及其精确控制和同步成为可能。这些脉冲允许研究孤立原子和凝聚物质系统中的电子动力学，其时间分辨率为物质中电子运动的自然时间尺度，并具有原子空间分辨率。就像拍摄飞行中的子弹等快速移动的物体的电影一样，需要用频闪方式组装许多帧，每一帧都构成物体的瞬时图像，时间域光谱学即将提供“电子电影”，能够以原子时空分辨率显示电子在物质中的运动及其发射。建议的研究将促进我们对(I)单电子和集体电子激发以及(Ii)层状半导体、吸附表面和纳米颗粒中电子和场的动力学的理解，促进新兴技术，如光波计算、纳米催化和人工光合作用，从而促进新型计算机和催化设备的发展，以确保我们的能源供应和保护我们的环境。秒级时间分辨光谱学导致了对孤立(气体)原子电离过程的令人印象深刻的时域研究，并有望显著提高我们对层状半导体结构和纳米颗粒的电子性质的理解。然而，时间分辨光电子能谱的物理解释面临着重大的概念挑战，需要进行全面的理论研究，即使对简单的原子系统也是如此。对于复杂的系统，如纳米粒子和固体表面，必须克服在描述瞬时光激电子动力学方面的额外严重的技术困难。拟议的工作应对这些挑战。它侧重于模拟电子的时间和空间分辨发射，以及从被吸附复盖的金属表面和纳米粒子产生上转换的高次谐波(HH)辐射。它继续发展和应用互补的量子力学方法，包括依赖时间的薛定谔方程的数值解，以及物理上更透明的半经典方法。它将评估时间和发射角度分辨的光电子和HH光谱能够揭示以下信息的保真度：(A)固体中的电子力和动力学，以及(B)入射光脉冲的非均匀纳米等离子体电场增强。该奖项反映了NSF的法定使命，并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，被认为值得支持。

项目成果

Enhanced cutoff energies for direct and rescattered strong-field photoelectron emission of plasmonic nanoparticles

• DOI: 10.1515/nanoph-2023-0120
• 发表时间: 2023-04-12
• 期刊: NANOPHOTONICS
• 影响因子: 7.5
• 作者: Saydanzad，Erfan;Powell，Jeffrey;Thumm，Uwe
• 通讯作者: Thumm，Uwe

Strong-field ionization of plasmonic nanoparticles

• DOI: 10.1103/physreva.106.033103
• 发表时间: 2022-09
• 期刊: Physical Review A
• 影响因子: 2.9
• 作者: E. Saydanzad;J. Li;U. Thumm

Breakdown of the single-collision condition for soft x-ray high harmonic generation in noble gases

• DOI: 10.1364/optica.471084
• 发表时间: 2022-12-20
• 期刊: OPTICA
• 影响因子: 10.4
• 作者: Chevreuil，Pierre-Alexis;Brunner，Fabian;Gallmann，Lukas
• 通讯作者: Gallmann，Lukas

Strong-Field Control of Plasmonic Properties in Core–Shell Nanoparticles

核壳纳米粒子等离激元特性的强场控制

• DOI: 10.1021/acsphotonics.2c00663
• 发表时间: 2022
• 期刊: ACS Photonics
• 影响因子: 7
• 作者: Powell, Jeffrey A.;Li, Jianxiong;Summers, Adam;Robatjazi, Seyyed Javad;Davino, Michael;Rupp, Philipp;Saydanzad, Erfan;Sorensen, Christopher M.;Rolles, Daniel;Kling, Matthias F.
• 通讯作者: Kling, Matthias F.