CDS&E: Excited-state properties and the impact of random defects in quantum materials

该奖项支持理论和计算研究以及技术教育，这些技术将增强和扩展我们目前对由单层原子组成的现实二维（2D）材料特性的科学知识。正如半导体的发现彻底改变了计算和信息存储一样，功能性2D材料和垂直堆叠2D材料形成的材料有可能彻底改变我们生活的各个方面。它们正在积极探索基础研究和现代设备应用，包括以最小的损失在国家电网中高效发电，存储和运输电力，能够同步监测的超灵敏传感器以及有效的疾病检测和诊断。实现这些新颖和变革性技术应用的关键是对2D材料中丰富的奇异相之间相互作用的基本理解。 由于电子-电子相互作用的复杂性以及材料的不均匀性，适用于完美块体材料的标准计算建模方法对于2D材料建模通常变得不可靠。PI和他的团队将开发和应用先进的理论和计算技术，以解释强电子-电子相互作用和二维材料的非均匀性，探索可能用于技术进步的物理特性和现象。该奖项还支持各种教育和推广活动。PI将（1）培养计算物理，数据科学和材料科学研究的本科生和研究生，（2）通过将研究与教学相结合，提供相应的跨学科实践材料建模课程，以及（3）开展教育推广活动，有可能在利哈伊谷加强科学教育，提高公众的科学意识和素养。理论和计算研究和技术教育，将增强和扩大我们目前的二维（2D）材料的属性超越理想模型的完美有序或结构平均的材料的科学知识。为了应对研究适度相关的现实2D材料的挑战，PI将开发和采用先进的数值和理论技术来解释库仑相互作用，随机无序，完整的轨道结构以及材料中介电屏蔽的存在。由于最近的实验发现，在二维量子材料中的几个开放的问题已经成为焦点，将被解决，如（1）什么是纳米级相共存材料的不完美性，空间相关性和库仑相互作用的物理性质？(2)在材料缺陷存在的情况下，库仑和激子相互作用以及对称性破缺状态附近的量子临界性的命运是什么？(3)缺陷引起的对称性破缺状态，例如，莫特物理和金属-绝缘体量子跃迁可以通过能带工程来利用吗？PI将开发实现各种对称性破缺状态之间缺陷诱导跃迁的潜力。该奖项还支持各种教育和推广活动。PI将（1）培养计算物理，数据科学和材料科学研究的本科生和研究生，（2）通过将研究与教学相结合，提供相应的跨学科实践材料建模课程，以及（3）执行教育推广与潜力，以加强STEM教育和提高公众的科学意识和素养在利哈伊谷。这个奖项反映了NSF的法定基金会的使命是履行其使命，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价，被认为值得支持。

NONTECHNICAL SUMMARYThis award supports theoretical and computational research and education on techniques that will enhance and expand our current scientific knowledge of the properties of realistic two-dimensional (2D) materials, which consist of a single layer of atoms. Just as the discovery of semiconductors revolutionized computation and information storage, functional 2D materials and materials formed by vertically stacking 2D materials have the potential to revolutionize every aspect of our lives. They are actively being explored for both fundamental research and modern device applications, including efficient generation, storing, and transporting power across the national grid with minimal losses, ultrasensitive sensors capable of synchronous monitoring, and efficient disease detection and diagnosis. Critical to actualizing these novel and transformative technological applications is a fundamental understanding of the interplay between the exotic phases that abound in 2D materials. Due to the complexity of electron-electron interactions coupled with materials' inhomogeneities, standard computational modeling approaches suitable for perfect bulk materials often become unreliable for modeling 2D materials. The PI and his team will develop and employ advanced theoretical and computational techniques that will account for strong electron-electron interaction and inhomogeneous nature of 2D materials to explore physical properties and phenomena that could potentially be harnessed for technological advances.This award also supports various education and outreach activities. The PI will (1) train both undergraduate and graduate students in computational physics, data science, and materials science research, (2) deliver corresponding interdisciplinary hands-on materials modeling courses by integrating research with teaching, and (3) perform educational outreach with the potential to enhance science education and increased public scientific awareness and literacy within the Lehigh Valley.TECHNICAL SUMMARYThis award supports theoretical and computational research and education on techniques that will enhance and expand our current scientific knowledge of the properties of two-dimensional (2D) materials beyond idealistic models of perfectly ordered or structurally averaged materials. To tackle the challenges of studying moderately correlated realistic 2D materials, the PI will develop and employ advanced numerical and theoretical techniques accounting for Coulomb interactions, random disorder, complete orbital structure, and the presence of dielectric screening within the material. Several open questions that have come into focus due to recent experimental discoveries in 2D-based quantum materials will be addressed, such as (1) What is the physical nature of the nanoscale phase coexistence between material’s imperfection, spatial correlations, and Coulomb interactions? (2) What is the fate of Coulomb and exciton interactions, and quantum criticality near broken symmetry states in the presence of material imperfection? (3) Can the defect-induced broken symmetry state, e.g., Mott physics and metal-insulator quantum transition be harnessed through band-engineering? The PI will exploit the potential to realize defect-induced transitions between the various broken-symmetry states.This award also supports various education and outreach activities. The PI will (1) train both undergraduate and graduate students in computational physics, data science, and materials science research, (2) deliver corresponding interdisciplinary hands-on materials modeling courses by integrating research with teaching, and (3) perform educational outreach with the potential to enhance STEM education and increased public scientific awareness and literacy within the Lehigh Valley.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.