Collaborative Research: Worm Algorithm and Diagrammatic Monte Carlo for Strongly Correlated Condensed Matter Systems

合作研究：强相关凝聚态系统的蠕虫算法和图解蒙特卡罗

• 批准号: 2335904
• 负责人: Boris Svistunov
• 金额: $ 49万
• 依托单位: University of Massachusetts Amherst
• 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: 2024-01-15 至 2026-12-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2335904&HistoricalAwards=false
• 关键词: Collaborative; Research; Worm; Algorithm; Diagrammatic

NONTECHNICAL SUMMARYThis award supports theoretical and computational studies of materials and systems in which their constituents (electrons, atoms, and ions) interact strongly with each other and, as a result, exhibit novel quantum behavior. The main research focus is on advancing fundamental understanding of unusual properties and phenomena which may lead to the development of future technologies. The PIs will employ advanced analytical methods and computational algorithms that they have developed to achieve accurate description of several key condensed matter systems at low temperature when collective quantum behavior of atoms and electrons results in the superconducting and superfluid states. Superconductivity and superfluidity are phenomena characterized by zero resistance and zero viscosity to the electron and fluid flows, respectively. These are related states of matter distinguished by the charge of the particles participating in the flow: in superconductors the flow is associated with charged electron pairs, while in superfluids it is due to the flow of neutral atoms such as, for example, Helium-4. In this project, various mechanisms responsible for superconductivity in prototypical systems and superfluidity in Helium-4 will be investigated. This project also supports training graduate students in advanced numerical techniques, quantum statistics, topical problems of condensed-matter and atomic physics, and high-performance computing. This project also helps to advance the Precision Many Body Physics Initiative which is aimed to facilitate international collaboration in cutting edge research directed toward understanding collective properties of matter, including quantum matter. Activities planned within this context include international workshops, Focused Sessions at American Physical Society March Meetings, and topical mini workshops.TECHNICAL SUMMARY This award supports theoretical and computational research with an aim to achieve a fundamental understanding of electronic and transport properties of a variety of condensed matter systems through the use of two state-of-the-art approaches to correlated quantum many-body systems: Worm Algorithm (WA) and Diagrammatic Monte Carlo (DiagMC); both introduced by the research team.The main goals of the project are: (i) WA-based studies of a new class of pseudo-one-dimensional superfluid systems called "transverse quantum fluids"; (ii) DiagMC studies of Cooper instability in the prototypical model of correlated electrons, uniform electron gas (with and without coupling to the phonon subsystem); and (iii) DiagMC studies of novel polaron and bipolaron states.This project also supports training graduate students in advanced numerical techniques, quantum statistics, topical problems of condensed-matter and atomic physics, and high-performance computing. This project also helps to advance the Precision Many Body Physics Initiative which is aimed to facilitate international collaboration in cutting edge research directed toward understanding collective properties of matter, including quantum matter. Activities planned within this context include international workshops, Focused Sessions at American Physical Society March Meetings, and topical mini workshops.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.

非技术总结该奖项支持对材料和系统的理论和计算研究，在这些材料和系统中，它们的组成成分(电子、原子和离子)相互作用强烈，因此表现出新的量子行为。主要的研究重点是促进对可能导致未来技术发展的不寻常性质和现象的基本理解。PI将使用他们开发的先进分析方法和计算算法，在原子和电子的集体量子行为导致超导和超流态时，在低温下实现对几个关键凝聚态的准确描述。超导性和超流性分别是电子和流体流动的零阻和零粘性现象。这些是物质的相关状态，通过参与流动的粒子的电荷来区分：在超导体中，流动与带电电子对有关，而在超流体中，它是由于中性原子的流动，例如氦-4。在这个项目中，我们将研究原型系统的超导电性和氦-4的超流性的各种机制。该项目还支持对研究生进行高级数值技术、量子统计、凝聚态和原子物理的主题问题以及高性能计算方面的培训。该项目还有助于推进精密多体物理倡议，该倡议旨在促进在尖端研究方面的国际合作，以了解包括量子物质在内的物质的集体性质。在此背景下计划的活动包括国际研讨会、美国物理学会3月会议上的重点会议和专题迷你研讨会。该奖项支持理论和计算研究，目的是通过使用两种最先进的方法来实现对各种凝聚态系统的电子和输运性质的基本理解：WORM算法(Wa)和图解蒙特卡罗(DiagMC)，这两种方法都是由研究小组介绍的。该项目的主要目标是：(I)基于Wa的一类新的伪一维超流体系统的研究，称为“横向量子流体”；(Ii)关联电子、均匀电子气(有或没有耦合到声子子系统)原型模型中库珀不稳定性的诊断MC研究；以及(Iii)新型极化子和双极化子状态的诊断MC研究。该项目还支持对研究生进行高级数值技术、量子统计、凝聚态和原子物理的主题问题以及高性能计算的培训。该项目还有助于推进精密多体物理倡议，该倡议旨在促进在尖端研究方面的国际合作，以了解包括量子物质在内的物质的集体性质。在此背景下计划的活动包括国际研讨会、美国物理学会3月份会议上的重点会议和专题迷你工作坊。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。