Non-perturbative studies of electron-lattice interactions in quantum materials

量子材料中电子晶格相互作用的非微扰研究

• 批准号: 2401388
• 负责人: Steven Johnston
• 金额: $ 35.13万
• 依托单位: University of Tennessee Knoxville
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-08-01 至 2027-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2401388&HistoricalAwards=false
• 关键词: Non; perturbative; studies; electron; lattice

Nontechnical Summary:Quantum materials represent a diverse class of systems at the forefront of materials research. These materials host several novel and highly tunable states of matter, each with transformative potential across different science and technology sectors. Modeling these systems is incredibly challenging, however, and often requires the development and use of advanced computational methods. This project focuses on performing state-of-the-art numerical simulations of quantum materials where the electrons interact strongly with the motion of the atoms. While these interactions are believed to play a key role in different families of quantum materials, previous numerical studies have often concentrated on oversimplified models with unrealistic parameters primarily for various technical reasons. This aspect has generally prevented the scientific community from obtaining definitive answers to how these interactions influence the properties of different materials. The PI’s team will leverage new simulation capabilities to perform detailed simulations of different quantum materials while including realistic descriptions of the interactions between the electrons and lattice of atoms that form the material. The team will also provide predictions for various spectroscopic measurements to guide future experiments on these materials. Combined, this project will help identify organizing principles for quantum materials and facilitate their use in future scientific and technological applications. This project will also broaden participation in computational science and provide training in cutting-edge computational methods to enhance the scientific workforce. For example, the PI’s team will develop new training materials and open-source codes for performing numerical simulations of quantum materials, which will be disseminated in partnership with the University of Tennessee’s Center for Advanced Materials & Manufacturing, an NSF MRSEC center. Finally, the PI will continue existing efforts aimed at increasing opportunities for underrepresented minorities in physics through partnerships with the APS Bridge and Nuclear Physics in Eastern Tennessee programs.Technical Summary:Understanding the properties of strongly correlated quantum materials is a forefront challenge for the scientific community. These materials often host strong electron-electron and electron-phonon (e-ph) interactions, which produce correlated electron liquids that defy theoretical descriptions based on single-particle theories. Modeling their behavior often requires nonperturbative numerical methods; however, addressing realistic e-ph interactions remains as a key challenge. This project addresses this problem by applying state-of-the-art quantum Monte Carlo methods to study broad classes of models for quantum materials hosting strong e-ph interactions, leveraging a new open-source implementation of the determinant quantum Monte Carlo (DQMC) algorithm developed by the PI’s group. This code can simulate a broad class of Hamiltonians and uses hybrid Monte Carlo methods to sample the phonon fields efficiently and overcome the long autocorrelation times typically associated with these simulations. The PI and his team will use these capabilities to perform numerically exact simulations of models beyond the canonical Holstein model with physically realistic descriptions of the phonon subsystem. Specifically, they will study how the e-ph coupling influences the emergent properties of materials ranging from unconventional superconductors to kagome metals to graphene-derived systems. They will also predict spectroscopic measurements on such systems to guide experimental studies and provide crucial validation of their results. A particular focus for this project is on generalized Su-Schrieffer-Heeger-like e-ph interactions, where the atomic motion couples the electron’s kinetic energy via a modulation of the overlap integral. This interaction has been linked to novel phenomena ranging from mobile (bi)polarons, high-temperature superconductivity, antiferromagnetism, novel charge or bond orders, and topological states of matter. This project will also broaden participation in computational science and provide training in cutting-edge computational methods to enhance the scientific workforce. For example, the PI’s team will develop new training materials and open-source codes for performing numerical simulations of quantum materials, which will be disseminated in partnership with the University of Tennessee’s Center for Advanced Materials & Manufacturing, an NSF MRSEC center. Finally, the PI will continue existing efforts to increase opportunities for underrepresented minorities in physics through partnerships with the APS Bridge and Nuclear Physics in Eastern Tennessee programs.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：量子材料代表了材料研究最前沿的潜水类系统。这些材料拥有几种新颖且高度可调的物质状态，每种状态在不同的科学和技术领域都具有变革性的潜力。但是，对这些系统进行建模非常具有挑战性，并且通常需要开发和使用先进的计算方法。该项目着重于对量子材料进行最新的数值模拟，其中电子产品与原子的运动有着强烈的相互作用。虽然这些相互作用被认为在不同的量子材料家族中起着关键作用，但由于各种技术原因，先前的数值研究通常集中于具有不切实际参数的过度简单模型。这方面通常阻止科学界获得这些相互作用如何影响不同材料的性质的确定答案。 PI的团队将利用新的模拟功能来对不同的量子材料进行详细的模拟，同时包括对形成材料的电子和原子晶格之间相互作用的现实描述。该团队还将为各种光谱测量值提供预测，以指导对这些材料的未来实验。该项目结合在一起，将有助于确定量子材料的组织原则，并促进其在未来的科学和技术应用中的使用。该项目还将扩大对计算科学的参与，并为提高科学劳动力的尖端计算方法提供培训。例如，PI的团队将开发新的培训材料和开源代码，以进行量子材料的数值模拟，该材料将与NSF MRSEC中心的田纳西大学高级材料与制造中心合作分发。最后，PI将继续努力通过与APS桥和田纳西州东部计划中的APS桥和核物理的合作伙伴关系来增加物理学不足的机会的现有努力。技术摘要：了解强相关的量子材料的特性是对科学社区的最前沿挑战。这些材料通常具有强烈的电子电子和电子 - 光（E-PH）相互作用，它们产生相关的电子液体，这些液体违反了基于单粒子理论的理论描述。对其行为进行建模通常需要非扰动数值方法。但是，解决现实的E-PH交互仍然是一个关键挑战。该项目通过应用最先进的量子蒙特卡洛方法来研究该问题，以研究托管强烈E-PH相互作用的量子材料的广泛类别，利用了由PI组开发的确定的量子蒙特卡洛（DQMC）算法的新开源实施。该代码可以模拟大量的汉密尔顿人，并使用混合蒙特卡洛方法有效地对光子场进行采样，并克服通常与这些模拟相关的较长自相关时间。 PI和他的团队将使用这些功能来对模型进行单独的模拟，除了对光子子系统的物理描述外，规范性荷斯坦模型之外。具体而言，他们将研究E-PH耦合如何影响从非常规超导体到Kagome Metals到石墨烯衍生系统的材料的新兴特性。他们还将预测此类系统上的光谱测量值，以指导实验研究并提供至关重要的结果验证。该项目的一个特殊重点是普遍的Su-Schrieffer-Heeger样E-PH相互作用，在该相互作用中，原子运动通过重叠积分的调制来使电子的动能融合在一起。这种相互作用与新型现象有关，从移动（BI）极性子，高温超导性，抗势力磁性，新型电荷或键订单以及物质的拓扑状态。该项目还将扩大对计算科学的参与，并为提高科学劳动力的尖端计算方法提供培训。例如，PI的团队将开发新的培训材料和开源代码，以进行量子材料的数值模拟，该材料将与NSF MRSEC中心的田纳西大学高级材料与制造中心合作分发。最后，PI将继续进行现有努力，以通过与田纳西州东部计划中的APS桥和核物理的合作伙伴关系来增加物理中代表性不足的机会。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子优点和更广泛的审查标准来通过评估来通过评估来获得的支持。