Novel Quantum Effects in Strongly Correlated Materials

该奖项支持研究和教育活动，旨在了解和预测量子材料中物质的新相，量子材料是具有大量粒子的物理系统，量子力学定律在这些系统中得到了更突出的体现。PI将研究电子行为非常奇怪的金属：在某些情况下，当它们在空间中沿特定方向移动时，它们就像没有质量一样传播；在另一些情况下，它们以完全不连贯的方式运动，以极快的时间尺度达到热平衡，与铜或铝等传统金属不同。当电子在材料中传播时，它们可以形成具有最不同性质的量子物质相。电子相互作用的方式可能导致物质的新状态；从不导电的金属到导电而不散热的超导体，甚至是电子像湍急的水流一样流动的状态。该项目的理论进展将加强对这些物质相的理解，并可能导致未来的设备技术和应用。该奖项还通过俄克拉荷马大学的NSF本科生研究体验计划支持PI面向本科生的外展活动，并通过NSF教师研究体验计划支持俄克拉荷马城大都市区的高中物理教师。PI还将参加俄克拉荷马州科学与数学学院的导师计划，这是俄克拉荷马州首屈一指的公立寄宿高中，专注于科学、技术、工程和数学学科，并将向公众提供关于科学的公开讲座。该奖项支持研究和教育活动，旨在加强我们对广泛的强关联系统中相互作用和新颖量子效应的基本理解，这些系统拥有非传统准粒子或完全不存在准粒子的概念。这项研究将集中在两个主要方面：1)非传统金属的关联，其中PI将探索节线半金属系统和半狄拉克费米子系统中新的量子临界现象和流体动力学行为，以及非相干金属的物理及其与各种强关联电子系统中奇怪金属相的可能关系。2)莫尔异质结构中的多体效应，其中PI将从理论上研究扭曲的石墨烯双层膜在魔角或附近的相互作用物理，其中超导电性和相关的绝缘行为已经在实验上观察到。该研究团队将研究在量子临界点附近出现的新型向列相超导相，Sachdev-Ye-Kitaev模型的推广，从实验响应函数的角度看奇怪金属相的性质，以及在扭曲的石墨烯双层中观察到的磁性和相关金属相。该奖项还支持PI通过俄克拉荷马大学的NSF本科生研究经验计划向本科生和通过NSF教师研究经验计划向俄克拉荷马城大都市区的高中物理教师推广活动。PI还将参加俄克拉荷马州首屈一指的公立STEM高中--俄克拉荷马科学与数学学院的导师计划，并将向公众提供关于科学的公开讲座。这一奖项反映了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。

NONTECHNICAL SUMMARY This award supports research and educational activities with an aim to understand and predict novel phases of matter in quantum materials, physical systems with a large number of particles where the laws of quantum mechanics are more prominently manifested. The PI will investigate metals where electrons can behave in very odd ways: In some cases they propagate as if they have no mass when they move in certain directions in space; in others, they move in a completely incoherent fashion, reaching thermal equilibrium at extremely fast time scales, unlike in conventional metals like copper or aluminum. As they propagate in materials, electrons can form phases of quantum matter with the most diverse properties. The way the electrons interact with each other can lead to novel states of matter; from metals that fail to conduct electricity to superconductors that conduct electricity without any dissipation of heat, or even regimes where electrons flow like a turbulent stream of water. The theoretical advances in this project will enhance the understanding of such phases of matter, and may lead to future device technologies and applications. This award also supports the PI's outreach activities to undergraduate students through the NSF Research Experience for Undergraduates program at the University of Oklahoma and to high school physics teachers in the metropolitan area of Oklahoma City through the NSF Research Experience for Teachers program. The PI will also enroll in the mentorship program at the Oklahoma School of Science and Mathematics, the premier public residential high school in the state of Oklahoma focused on Science, Technology, Engineering, and Mathematics disciplines, and will offer open lectures about science to the general public. TECHNICAL SUMMARY This award supports research and educational activities with an aim to enhance our fundamental understanding about interactions and novel quantum effects in a broad class of strongly correlated systems that host unconventional quasiparticles or where the concept of quasiparticles is entirely absent. The research will be focused on two main thrusts: 1) Correlations in unconventional metals, where PI will explore novel quantum critical phenomena and hydrodynamic behavior in systems with nodal-line semimetals and systems with semi-Dirac fermions, and the physics of incoherent metals and their possible relation to strange metal phases in various strongly correlated electron systems. 2) Many-body effects in Moire heterostructures, where the PI will theoretically examine the physics of interactions in twisted graphene bilayers at or near the magic angle, where superconductivity and correlated insulating behavior have been experimentally observed. The research team will investigate novel nematic superconducting phases emerging in the vicinity of quantum critical points, generalizations of the Sachdev-Ye-Kitaev model, the nature of strange metal phases from the point of view of experimental response functions, and the magnetic and correlated metallic phases observed in twisted graphene bilayers.This award also supports the PI's outreach activities to undergraduate students through the NSF Research Experience for Undergraduates program at the University of Oklahoma and to high school physics teachers in the metropolitan area of Oklahoma City through the NSF Research Experience for Teachers program. The PI will also enroll in the mentorship program at the Oklahoma School of Science and Mathematics, the premier public residential STEM high school in the state of Oklahoma, and will offer open lectures about science to the general public.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.