Charge Fluctuations and Competing Orders in Strongly Correlated Materials

强相关材料中的电荷波动和竞争顺序

• 批准号: 1707785
• 负责人: Dragana Popovic
• 金额: $ 35万
• 依托单位: Florida State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-15 至 2022-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1707785&HistoricalAwards=false
• 关键词: Charge; Fluctuations; Competing; Orders; Strongly

Non-Technical Abstract:Electronic properties of many new materials with potentially great technological importance are dominated by interactions among charge carriers. Those correlations give rise to a variety of phenomena of current interest in condensed matter physics, including the emergence of novel states of matter. These effects are most pronounced near transitions between different phases - conductor to insulator, or superconductor to normal - that can be tuned by an external parameter, like magnetic or electric field. The underlying quantum nature of those transitions contributes to the complexity of the observed behaviors. This research addresses fundamental questions about the nature and the dynamics of several charge-ordered states in the presence of other, competing phases, especially in the vicinity of quantum phase transitions. Most of the experiments involve measurements of charge transport, including various time-dependent protocols, using either electric or extremely high magnetic fields to tune through the phase transitions in two-dimensional crystals and high-temperature superconductor materials. A key component of the project is education and training of a diverse group of young researchers for future careers in academia, national laboratories, and industry. It also incorporates various activities to broaden the participation of underrepresented groups in the areas of science, technology, engineering, and mathematics.Technical Abstract:Many unusual properties of strongly correlated materials have been attributed to the proximity of quantum critical points, where different types of orders compete and coexist, and may even give rise to novel phases. The role of collective fluctuations near quantum critical points is thus increasingly recognized as one of the key questions in the physics of strongly correlated systems. Even though fluctuations of various charge-ordered states have been of particular interest, e.g. to clarify their relationship with high-temperature superconductivity in cuprates, there have been few studies of charge, as opposed to spin, dynamics. The aim of the project is to bridge this gap by using time-resolved charge transport measurements on very long time scales, proven to be powerful probes of out-of-equilibrium or glassy charge dynamics, quantum critical points, and novel, intermediate phases. The research is designed to provide answers to several fundamental questions in condensed matter physics concerning the interplay of charge correlations and disorder, their relationship to high-temperature superconductivity, and the nature of various ground states and quantum critical points, such as the two-dimensional metal-insulator transition and the magnetic-field-tuned superconducting transition in cuprates. This knowledge is essential to the development of condensed matter subfields of strongly correlated materials and out-of-equilibrium phenomena.

非技术摘要：许多具有潜在重大技术重要性的新材料的电子特性由电荷载流子之间的相互作用主导。 这些相关性引起了凝聚态物理学中当前感兴趣的各种现象，包括新物质状态的出现。 这些效应在不同相位之间的过渡（导体到绝缘体，或超导体到正常状态）附近最为明显，可以通过外部参数（如磁场或电场）进行调整。 这些跃迁的潜在量子性质导致了所观察到的行为的复杂性。 这项研究解决了一些电荷有序态的性质和动力学的基本问题，在其他竞争阶段的存在下，特别是在附近的量子相变。 大多数实验涉及电荷传输的测量，包括各种时间依赖性协议，使用电场或极高的磁场来调整二维晶体和高温超导材料的相变。 该项目的一个关键组成部分是教育和培训一批不同的年轻研究人员，为未来在学术界，国家实验室和工业界的职业生涯。 它还包括各种活动，以扩大在科学，技术，工程和数学领域的代表性不足的群体的参与。技术摘要：强关联材料的许多不寻常的属性已被归因于量子临界点，不同类型的订单竞争和共存的接近，甚至可能产生新的阶段。因此，量子临界点附近的集体涨落的作用越来越被认为是强关联系统物理学中的关键问题之一。尽管各种电荷有序态的涨落特别令人感兴趣，例如为了澄清它们与铜酸盐中高温超导性的关系，但很少有人研究电荷动力学，而不是自旋动力学。该项目的目的是通过在很长的时间尺度上使用时间分辨的电荷传输测量来弥合这一差距，该测量已被证明是失衡或玻璃态电荷动力学、量子临界点和新型中间相的强大探针。该研究旨在回答凝聚态物理学中的几个基本问题，涉及电荷相关性和无序的相互作用，它们与高温超导性的关系，以及各种基态和量子临界点的性质，例如二维金属-绝缘体转变和磁场调谐铜酸盐超导转变。这一知识对于强相关材料和非平衡现象的凝聚态子领域的发展至关重要。

项目成果

Nontrivial Fermi surface topology of the kagome superconductor CsV3Sb5 probed by de Haas–van Alphen oscillations

通过德哈斯范阿尔芬振荡探测 Kagome 超导体 CsV3Sb5 的非平凡费米表面拓扑

• DOI: 10.1103/physrevb.105.024508
• 发表时间: 2022
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Shrestha, K.;Chapai, R.;Pokharel, Bal K.;Miertschin, D.;Nguyen, T.;Zhou, X.;Chung, D. Y.;Kanatzidis, M. G.;Mitchell, J. F.;Welp, U.
• 通讯作者: Welp, U.

Fermiology of the Dirac type-II semimetal candidates (Ni,Zr) Te2 using de Haas–van Alphen oscillations

• DOI: 10.1103/physrevb.106.075154
• 发表时间: 2022-08
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: T. H. Nguyen;N. Aryal;Bal K. Pokharel;L. Harnagea;D. Mierstchin;D. Popović;D. Graf;K. Shrestha

Transport signatures of fragile glass dynamics in the melting of the two-dimensional vortex lattice

二维涡晶格熔化过程中易碎玻璃动力学的输运特征

• DOI: 10.1103/physrevb.107.014509
• 发表时间: 2023
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Maccari, I.;Pokharel, Bal K.;Terzic, J.;Dutta, Surajit;Jesudasan, J.;Raychaudhuri, Pratap;Lorenzana, J.;De Michele, C.;Castellani, C.;Benfatto, L.
• 通讯作者: Benfatto, L.

Collective Dynamics and Strong Pinning near the Onset of Charge Order in La1.48Nd0.4Sr0.12CuO4

La1.48Nd0.4Sr0.12CuO4 中电荷序开始附近的集体动力学和强钉扎

• DOI: 10.1103/physrevlett.120.156602
• 发表时间: 2018
• 期刊: Physical Review Letters
• 影响因子: 8.6
• 作者: Baity, P. G.;Sasagawa, T.;Popović, Dragana
• 通讯作者: Popović, Dragana