Strong Electron Correlations and Quantum Critical Phenomena

强电子相关性和量子临界现象

• 批准号: 0605769
• 负责人: Philip Phillips
• 金额: $ 44万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-15 至 2012-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0605769&HistoricalAwards=false
• 关键词: Strong; Electron; Correlations; Quantum; Critical

This award supports theoretical research and education in condensed matter physics with a focus on aspects of strongly correlated electron phenomena. Three key ideas lie at the heart of this project: 1) spectral weight transfer across the Mott gap suggests that the correct low-energy theory of doped Mott insulators involves a charge 2e bosonic field, 2) the suppression of the Josephson effect in nanowires below a critical diameter originates from the onset of a superconducting state with a pairing symmetry that is orthogonal to the s-wave state in the leads, and 3) the origin of the metallic state in thin metal film alloys displaying a putative insulator-superconductor transition is driven by glassiness. The goal of this project is to confirm and elucidate each of these ideas. This project focuses on developing theoretical tools and new ideas to elucidate key experimental systems that are dominated by large Coulomb repulsions or systems near quantum critical points. Of course in the presence of disorder, new phases are possible, such as glasses. Precisely how metallic phases obtain in two dimensions for either bosons or fermions is not known. This project continues to develop a possible resolution of this problem, as well as a systematic way of approaching many aspects of the strongly correlated problem. Broader Impact: This award supports graduate students seeking their PhD degrees in theoretical solid state physics. As the large Coulomb repulsion and disorder problems are central to solid state physics, it is essential that students gain expertise in this area. In addition to the training of graduate students, several other broad educational goals will be met. First, as a result of the PI's commitment to the communication of the current status of theoretical solid state physics to the next generation of students, he has written a much-needed graduate textbook, "Advanced Solid State Physics." The PI plans a new edition will which will incorporate new material on strongly correlated systems which helps integrate forefront research into an educational text. A new course at Illinois, entitled "Quantum Phase Transitions," has been developed as a direct outgrowth from NSF-funded research. A second important feature of this project is the PI's impact as a highly visible and effective role model for minority students in the Department of Physics and the College of Engineering (COE) at Illinois. A novel outreach component of the project is the PI's involvement in assisting scientists in developing countries. He recently organized an international workshop in Trinidad and Tobago on "Mottness and Quantum Criticality" which helped to introduce scientists from the Caribbean to frontier problems in strongly correlated electron materials. In addition, the PI is the Chair of the organizing committee for the symposium and educational and museum outreach for the 50th anniversary of the publication of the Bardeen-Cooper-Schrieffer theory of superconductivity. NON-TECHNICAL SUMMARY:This award supports theoretical research and education in condensed matter physics. The proposal focuses on the discovery and understanding of new states of matter that occur when the interactions among electrons are very large and lead to strong correlations in their motion. High temperature superconductors are examples of a class of materials in which strong interactions among electrons lead to new states of matter. Among the states of matter that the PI will study are the insulating state that arises as a consequence of strong interactions among electrons, known as a Mott insulator, and new states of matter that may be hidden in a transformation that takes place between superconducting and insulating states observed in thin films. The PI will focus on developing theoretical tools and new ideas to elucidate the underlying physics of key experimental systems and to understand how new metallic states arise.The PI is a highly visible and effective role model for minority students in the Department of Physics and the College of Engineering (COE) at Illinois. This award supports some of his education and outreach activities, including graduate level education in theoretical condensed matter physics with a focus on central problems of the field. The PI's research will contribute to his work to create a new edition of his graduate level textbook, "Advanced Solid State Physics," which will incorporate new material and integrate forefront research into the text. The PI activities in assisting scientists in developing countries to modernize their research constitute an outreach component of this project. His activities as Chair of the organizing committee for the symposium and educational and museum outreach for the 50th anniversary of the publication of the Bardeen-Cooper-Schrieffer theory of superconductivity are another component of his outreach efforts.

该奖项支持凝结物理学的理论研究和教育，重点是强相关的电子现象的各个方面。该项目的核心是三个关键想法：1）频谱重量转移跨莫特缝隙，表明，掺杂的莫特绝缘子的正确低能量理论涉及一个费用2e玻感领域，2）抑制纳米线的约瑟夫森效应，在关键的直径下是从一个重要的状态起源于一个超过态度的对称性的纳米线，该状态是造成对称性的，或者是对对称性的范围。 3）在薄金属膜合金中，金属状态的起源显示出假定的绝缘子 - 渗透导体过渡是由玻璃驱动的。该项目的目的是确认和阐明这些想法中的每一个。该项目着重于开发理论工具和新想法，以阐明由量子关键点附近的大型库仑排斥或系统主导的关键实验系统。当然，在存在障碍的情况下，可能是可能的，例如眼镜。尚不清楚金属相在两个维度上的金属阶段如何在两个维度中获得。该项目继续开发出可能解决此问题的可能解决方案，以及一种系统的方法，可以解决紧密相关问题的许多方面。更广泛的影响：该奖项支持研究生在理论固态物理学领域寻求博士学位的学位。由于较大的库仑排斥和混乱问题是固态物理学的核心，因此学生必须在这一领域获得专业知识。除了培训研究生外，还将实现其他几个广泛的教育目标。首先，由于PI致力于将理论固态物理学当前状态与下一代学生进行交流的承诺，因此他写了一本急需的研究生教科书“先进的固态物理学”。 PI计划将新版本将结合在密切相关的系统上的新材料，这有助于将前沿研究整合到教育文本中。伊利诺伊州的一门新课程名为“量子相变”，已开发为NSF资助的研究的直接产生。该项目的第二个重要特征是PI的影响是伊利诺伊州物理学系和工程学院（COE）的少数族裔学生的高度可见和有效的榜样。该项目的新型外展部分是PI参与协助发展中国家的科学家。他最近在特立尼达和多巴哥组织了一个国际研讨会，以“ Mottness and Quantum Critistity”组织，这有助于将来自加勒比海的科学家介绍到密切相关的电子材料中的边境问题。此外，PI是Bardeen-Cooper-Schrieffer超导性理论成立50周年的研讨会和教育和博物馆外展组织主席。非技术摘要：该奖项支持凝结物理学的理论研究和教育。该提案的重点是对电子之间的相互作用非常大并导致其运动相关性的发现和理解。 高温超导体是一类材料的例子，其中电子之间的强烈相互作用导致了物质的新状态。在物质的状态下，PI将研究的是绝缘状态，该状态是由于电子之间强烈相互作用（称为Mott绝缘子）而产生的，而物质的新状态可能隐藏在薄膜中观察到的超导和绝缘状态之间发生的转化中。 PI将着重于开发理论工具和新想法，以阐明关键实验系统的基本物理，并了解新的金属状态如何出现。该奖项支持他的一些教育和外展活动，包括理论上凝结物理学中的研究生教育，重点是该领域的中心问题。 PI的研究将有助于他创建他的研究生水平教科书“ Advanced Solid State Physics”的新版本，该版本将结合新材料并将前沿研究整合到本文中。 PI协助发展中国家现代化研究的PI活动构成了该项目的外展部分。他担任组织和教育和博物馆外展组织委员会主席的活动，曾在Bardeen-Cooper-Schrieffer超导性的50周年纪念日纪念日，是他推广工作的另一个组成部分。