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.

光电子发射是自然界中基本的光与物质相互作用过程。它发生在波长足够短、强度足够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特性的信息。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丰富的方法之一，重要地促进了激光和探测技术以及精确量子力学理论方法的发展。能域光谱对光发射过程中样品的时间平均内部电子动力学进行成像，但不能解析光电子释放（或再散射）过程中的超快时间相关电子动力学。所提出的理论工作是由超快激光技术的非凡进步推动的，该技术能够产生超短光脉冲及其精确控制和同步。这些脉冲允许研究孤立原子和凝聚态物质系统中的电子动力学，具有物质中电子运动的自然时间尺度的时间分辨率和原子空间分辨率。就像拍摄快速移动物体（例如飞行中的子弹）的电影一样，需要对许多帧进行频闪组合，每个帧构成物体的瞬时图像，时域光谱将提供“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。拟议的研究将增进我们对（i）单电子和集体电子激发以及（ii）层状半导体、吸附物覆盖表面和纳米粒子中的电子和场动力学的理解，促进光波计算、纳米催化和人工光合作用等新兴技术的发展，从而有助于新型计算机和催化装置的发展 确保我们的能源供应和保护我们的环境。阿秒时间分辨光谱学对孤立（气态）原子的电离过程进行了令人印象深刻的时域研究，预计将显着增进我们对层状半导体结构和纳米颗粒电子特性的理解。然而，时间分辨光电子光谱的物理解释面临着重大的概念挑战，并且需要全面的理论研究，即使对于简单的原子系统也是如此。对于复杂的系统，例如纳米粒子和固体表面，必须克服描述瞬态光激发电子动力学的额外严重技术困难。拟议的工作解决了这些挑战。它专注于对电子的时间和空间分辨发射进行建模，以及从吸附物覆盖的金属表面和纳米粒子生成上转换高次谐波 (HH) 辐射。它通过开发和应用互补的量子力学方法来进行，包括瞬态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分辨光电子和 HH 光谱可以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价值和更广泛的影响审查进行评估，被认为值得支持 标准。

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.