Bad Metal Behavior and the Metal Insulator Transition

非技术性总结对控制材料电性能的因素的探索一直是我们今天所知的大部分物理科学的驱动力。该奖项支持介于金属和绝缘体之间的材料的理论和计算研究和教育。PI将使用先进的计算技术来研究具有彼此强烈相互作用的电子的材料，并且在其结构或化学中包含许多缺陷，这些缺陷反映在电子的环境中。 这是了解金属，绝缘体和可能存在于它们之间的电子物质的新状态的基础研究。在金属和绝缘体之间的这个中间区域，材料表现出质的不同的物理行为，对其的理解需要新的理论和计算工具。这项研究可能有助于未来器件技术的知识基础，并开发新的战略，以发现具有所需电子特性的新材料。该项目将允许在理论和计算凝聚态物理学方面培养研究生。研究所会继续透过不同的外展活动，向公众披索和加强对科学和技术的认识，以及研究的重要性。这些措施包括：（1）在小学举办讲座，以普及科学和技术，并使年轻学生能够接触到最新的发现;（2）PI将在年度地区科学博览会上担任评委。参加这些展览会的有该地区公立和私立学校的K-12学生;（3）PI还将与高中暑期实习生合作，作为“佛罗里达青年学者”计划的一部分，使他们能够通过开发JAVA动画和其他网络，该奖项支持介于金属和绝缘体之间的材料的理论和计算研究和教育。金属和绝缘体之间的这种所谓的“坏金属”状态由非弹性电子-电子散射主导，并且表现出与任一相定性不同的行为。无序和不均匀性对这种强相关物质的影响正迅速成为材料科学的核心问题之一，因为实验探针的最新进展允许在纳米尺度上直接可视化，并提供了令人信服的证据，表明大多数接近金属-绝缘体转变的系统比以前假设的更不均匀。PI将从理论上研究金属-绝缘体转变的几个关键方面，这些方面已经通过最近的实验工作得到关注。 本论文的研究重点是回答以下问题：（1）有限温度下强关联金属与Mott绝缘体之间纳米尺度相共存的物理本质是什么？(2)与莫特-安德森跃迁相关的“电子格里菲思相”的物理学是否可以用强无序重整化群思想来处理，这是其他无序主导的量子临界点的首选工具？价键形成和近藤屏蔽之间的竞争如何在这种无序驱动的非费米液体区域中表现出来？(3)描述长程库仑相互作用的强几何阻挫在产生各种电子不均匀相（有无无序）中的作用是什么？该项目将允许在理论和计算凝聚态物理学方面对研究生进行培训。研究所会继续透过不同的外展活动，向公众披索和加强对科学和技术的认识，以及研究的重要性。这些措施包括：（1）在小学举办讲座，以普及科学和技术，并使年轻学生能够接触到最新的发现;（2）PI将在年度地区科学博览会上担任评委。这些展览会涉及该地区公立和私立学校的K-12学生;（3）PI还将与高中暑期实习生合作，作为“佛罗里达青年学者”计划的一部分，使他们能够通过开发JAVA动画和其他基于网络的材料将尖端科学带给广大公众。

NON-TECHNICAL SUMMARYThe quest to understand what controls the electrical properties of materials has been the driving force for much of the physical science as we know it today. This award supports theoretical and computational research and education on materials that are somewhere between metals and insulators. The PI will use advanced computational techniques to study materials which have electrons that interact strongly with each other and contain many imperfections in their structure or chemistry that are reflected in the environment of the electrons. This is fundamental research to understand the nature of metals, insulators, and new states of electronic matter that may exist between them. In this intermediate region between metals and insulators, materials display qualitatively different physical behavior, the understanding of which requires new theoretical and computational tools. This research may contribute to the intellectual foundations of future device technologies and to developing new strategies to discover new materials with desired electronic properties.This project will allow training of graduate students in theoretical and computational condensed matter physics. The PI will continue to promote and enhance scientific and technological understanding and importance of our research to the general public through various outreach activities. These will include: (1) Presenting lectures at elementary schools in order to popularize science and technology, and bring the most recent discoveries within reach of young students; (2) The PI will act as a judge at annual regional Science Fairs. These fairs involve K-12 students from public and private schools within the region; (3) The PI will also be working with high-school summer interns as a part of the "Florida Young Scholar" program, enabling them to bring cutting-edge science to the public at large through the development of JAVA animations and other web-based materials.TECHNICAL SUMMARYThis award supports theoretical and computational research and education on materials that are somewhere between metals and insulators. This so-called "bad-metal" regime between a metal and an insulator is dominated by inelastic electron-electron scattering, and shows behavior qualitatively different from either phase. The impact of disorder and inhomogeneity on such strongly correlated matter is rapidly becoming one of the central issues in materials science, as recent advances in experimental probes allow direct visualization on the nanoscale and have provided compelling evidence that most systems near the metal-insulator transition are much more inhomogeneous than previously assumed. The PI will theoretically examine several key aspects of the metal-insulator transition that have come to focus through recent experimental work. The research will be focused on providing answers to the following questions: (1) What is the physical nature of the nanoscale phase coexistence between a strongly correlated metal and a Mott insulator at finite temperature? (2) Can the physics of "Electronic Griffiths phases" associated with Mott-Anderson transitions be tackled using strong disorder renormalization group ideas, which are the tools of choice for other disorder-dominated quantum critical points? How does the competition between valence-bond formation and Kondo screening manifest itself in such disorder-driven non-Fermi liquid regimes? (3) What is the role of strong geometric frustration characterizing the long-range Coulomb interaction in producing a variety of electronically inhomogeneous phases with and without disorder?This project will allow training of graduate students in theoretical and computational condensed matter physics. The PI will continue to promote and enhance scientific and technological understanding and importance of our research to the general public through various outreach activities. These will include: (1) Presenting lectures at elementary schools in order to popularize science and technology, and bring the most recent discoveries within reach of young students; (2) The PI will act as a Judge at annual regional Science Fairs. These fairs involve K-12 students from public and private schools within the region; (3) The PI will also be working with high-school summer interns as a part of the "Florida Young Scholar" program, enabling them to bring cutting-edge science to the public at large through the development of JAVA animations and other web-based materials.