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.

该奖项支持理论和计算研究和教育，其目标是在微观水平上理解材料和纳米结构的电子，光学和磁性，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来自于构成材料的电子和离子的相互作用。理解这些相互作用是现代技术的核心，如电子学，光电子学，光电子学和能量转换设备。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，这些性质可以显著改变，并且可以出现新的现象。该项目的重点是使用量子理论，建模和模拟，使用分析和计算工具来解释和预测新材料和纳米结构的存在和性质。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第一原理（即，没有经验参数）对材料行为的解释和预测，包括原子薄材料、纳米结构、界面和缺陷现象、新超导体和光催化材料。教育部分的重点是培养学生（研究生和本科生）和博士后研究员在当前的量子技术革命的研究和开发。该项目开发的计算工具将被纳入若干软件包，这些软件包将在网上免费提供给研究界。另一项教育活动与公众教育有关，通过在非专业媒体上发表文章和访谈以及通过PI和共同PI的公开讲座进行。该奖项支持理论和计算研究和教育，通过执行第一原理量子计算，在微观水平上理解材料和纳米结构的电子，传输，光学和磁性。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; 3）电子-声子耦合，光-物质相互作用和超导性。主要目标是使用多体量子理论，高性能计算和新的概念，如那些从拓扑结构来解释和预测的性质和现象，在真实的材料，包括低维系统。基于多体量子理论的几种最先进的方法被用来对真实的材料进行精确的第一性原理计算。基态性质得到使用从头赝势密度泛函理论形式主义。激发态性质的计算从相互作用的单粒子绿色的功能内的GW近似准粒子激发和相互作用的两个粒子绿色的功能通过Bethe-Salpeter方程的光学性能。电子-声子耦合计算使用一种新的方法的基础上GW微扰理论。用另一种新发展的含时绝热GW方法计算了驱动场作用下的含时现象和非线性光学响应。大量的属性被显示为可以使用上述方法访问。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、振动和机械性质、磁性、输运性质、泵浦-探测光谱、非线性光学响应和常规超导体的性质。理论和方法的发展也进行了进一步推进我们的概念和计算能力。第一性原理计算在适当的时候增加了模型哈密顿研究，特别是为了理解拓扑效应和具有更强电子关联的系统。教育部分侧重于培训学生（研究生和本科生）和博士后研究员，以研究和开发当前的量子技术革命。从该项目开发的计算工具将被纳入三个开源软件包-伯克利GW，PARATEC和EPW -这是免费提供给网络上的社区。另一项教育活动与公众教育有关，通过在非专业媒体上发表的文章和访谈以及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。