Theoretical Solid State Physics

理论固体物理

• 批准号: 2325410
• 负责人: Marvin Cohen
• 金额: $ 100万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-11-01 至 2027-10-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2325410&HistoricalAwards=false
• 关键词: Theoretical; Solid; State; Physics

NONTECHNICAL SUMMARYThis award supports theoretical and computational research and education with the goals of understanding the electronic, optical, and magnetic properties of materials and nanostructures at the microscopic level, predicting new materials and phenomena, and educating young scientists for research in this field. The fascinating properties and phenomena of condensed matter emerge from mutual interactions of the electrons and ions that make up materials. Understanding these interactions are central to modern technologies such as electronics, optoelectronics, photovoltaics, and energy conversion devices in general. These properties can be dramatically altered, and new phenomena can emerge, by varying the chemical composition or confining the materials to nanometer scales or exploring materials at the one- or two-dimensional level. This project is centered on using quantum theory, modeling, and simulations using analytical and computational tools to explain and predict the existence and properties of novel materials and nanostructures. New theoretical approaches and the availability of modern high-performance computers allow the team to obtain first-principles (i.e., with no empirical parameters) explanations and predictions of the behavior of materials including atomically thin materials, nanostructures, interfacial and defect phenomena, new superconductors, and photocatalytic materials. The educational component is focused on preparing students (graduate and undergraduate) and postdoctoral fellows for research and development in the current quantum technological revolution. The computational tools developed from the project will be incorporated into several software packages, which are made freely available on the web to the research community. Another educational activity is related to public education, which is done through articles and interviews published in lay media and via public lectures by the PI and co-PI. TECHNICAL SUMMARYThis award supports theoretical and computational research and education towards understanding the electronic, transport, optical, and magnetic properties of materials and nanostructures at the microscopic level by performing first-principles quantum calculations. The research is grouped into three topical areas of condensed matter physics and materials science: 1) novel phases and structures of materials; 2) optical and spin physics of reduced-dimensional systems, and 3) electron-phonon coupling, light-matter interaction, and superconductivity. The major objective is to use many-body quantum theory, high-performance computing, and new concepts such as those from topology to explain and predict the properties of and phenomena in real materials, including lower dimensional systems. Several state-of-the-art approaches based on many-body quantum theory are employed to enable accurate first-principles calculations for real materials. Ground-state properties are obtained using the ab initio pseudopotential density functional theory formalism. Excited-state properties are calculated from the interacting one-particle Green's function within the GW approximation for quasiparticle excitations and the interacting two-particle Green's function via the Bethe-Salpeter equation for optical properties. Electron-phonon couplings are computed using a new methodology based on GW perturbation theory. Time-dependent phenomena under driven fields and nonlinear optical responses are computed using another newly developed time-dependent adiabatic GW method. A host of properties are shown to be accessible with the above methods. Examples include structural information, electronic structure, energy gaps, optical and photoemission spectra, electronic topological invariants, surface and interface characteristics, vibrational and mechanical properties, magnetic properties, transport properties, pump-probe spectroscopies, nonlinear optical responses, and properties of conventional superconductors. Theoretical and methodological developments are also carried out to further advance our conceptual and computational capabilities. The first-principles calculations are augmented with model Hamiltonian studies when appropriate, especially for understanding topological effects and systems with stronger electron correlations.The educational component is focused on training of students (graduate and undergraduate) and postdoctoral fellows for research and development in the current quantum technological revolution. The computational tools developed from the project will be incorporated into three open-source software packages - Berkeley GW, PARATEC, and EPW - which are freely available to the community on the web. Another educational activity is related to public education, which is done through articles and interviews published in lay media and via public lectures by the PI and co-PI.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.

非技术摘要该奖项支持理论和计算研究和教育，目的是在微观水平上了解材料和纳米结构的电子、光学和磁性特性，预测新材料和现象，并教育年轻科学家进行该领域的研究。凝聚态物质的迷人特性和现象是由构成材料的电子和离子的相互作用产生的。了解这些相互作用对于电子、光电子、光伏和能源转换设备等现代技术至关重要。通过改变化学成分或将材料限制在纳米尺度或在一维或二维水平上探索材料，这些特性可以发生巨大的改变，并且可以出现新的现象。该项目的重点是利用量子理论、建模和模拟，利用分析和计算工具来解释和预测新型材料和纳米结构的存在和特性。新的理论方法和现代高性能计算机的可用性使团队能够获得材料行为的第一原理（即没有经验参数）解释和预测，包括原子薄材料、纳米结构、界面和缺陷现象、新型超导体和光催化材料。教育部分的重点是让学生（研究生和本科生）和博士后研究员为当前量子技术革命的研究和开发做好准备。该项目开发的计算工具将被纳入多个软件包中，这些软件包可以在网络上免费提供给研究界。另一项教育活动与公共教育有关，这是通过在非专业媒体上发表的文章和采访以及首席研究员和联合首席研究员的公开讲座来完成的。技术摘要该奖项支持理论和计算研究及教育，旨在通过执行第一原理量子计算，在微观层面上了解材料和纳米结构的电子、传输、光学和磁性特性。该研究分为凝聚态物理和材料科学的三个主题领域：1）材料的新相和结构； 2) 降维系统的光学和自旋物理学，以及 3) 电子声子耦合、光与物质相互作用和超导。主要目标是利用多体量子理论、高性能计算和拓扑学等新概念来解释和预测真实材料（包括低维系统）的特性和现象。采用几种基于多体量子理论的最先进方法来实现对真实材料的精确第一原理计算。基态性质是使用从头算赝势密度泛函理论形式获得的。激发态性质是通过准粒子激发的 GW 近似内相互作用的单粒子格林函数和通过光学性质的 Bethe-Salpeter 方程计算相互作用的两粒子格林函数。使用基于引力波微扰理论的新方法计算电子声子耦合。使用另一种新开发的时间相关绝热引力波方法计算驱动场和非线性光学响应下的时间相关现象。显示可以通过上述方法访问许多属性。例子包括结构信息、电子结构、能隙、光学和光电发射光谱、电子拓扑不变量、表面和界面特性、振动和机械特性、磁性、传输特性、泵浦探针光谱、非线性光学响应和传统超导体的特性。理论和方法的发展也旨在进一步提高我们的概念和计算能力。第一性原理计算在适当的时候通过模型哈密顿研究得到增强，特别是为了理解拓扑效应和具有更强电子相关性的系统。教育部分的重点是培训学生（研究生和本科生）和博士后研究员，以在当前的量子技术革命中进行研究和开发。该项目开发的计算工具将被纳入三个开源软件包——Berkeley GW、PARATEC 和 EPW——这些软件包可在网络上免费提供给社区。另一项教育活动与公共教育相关，通过在普通媒体上发表的文章和采访以及 PI 和 co-PI 的公开讲座来完成。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。