Quantum Critical Phenomena and Non-Fermi-Liquid Physics

[00:8107 . 75]这项资助支持一位杰出的、处于职业生涯中期的PI在强相关电子系统方面的理论工作。本基金资助的研究项目包括：(1)无序与量子临界现象；(2)高温超导现象；(3)高度相关系统中的非平衡现象。这类问题通常被称为非费米液体效应。它们超出了朗道费米液体理论对金属中电子的理解。超出费米液体理论的异常包括稀土合金中大量的热力学/量热结果，这些结果被认为是由于无序而接近量子临界点。在高密度磁记忆材料和弛豫铁电体中也有相关的效应。高Tc铜氧化物存在高温电阻率等非平衡效应。这些项目包括分析和数值方法以及与相关实验工作的密切联系。本基金支持的理论工作来自当前材料研究的两个主题。金属中电子的性质有一些异常，这显然超出了被称为朗道金属理论的传统范式。它们是由实际无序和/或极端环境（如压力、磁场或温度）的存在引起的。这里的工作是基础的和深远的，因为它可能需要开发复杂的、新的数学工具，同时它是由需要理解对高密度磁存储器或使用其铁电特性用于存储器应用的材料的重要材料所驱动的。这项工作将在实验人员的密切联系下进行，必要时将使用分析和数值技术

0081075MillisThis grant supports the theoretical work of a distinguished, mid-career PI on stronglyCorrelated electron systems. The list of research projects in this grant includes (1)Disorder and Quantum Critical Phenomena, (2) High Temperature Superconductivity and(3) Nonequilibrium phenomena in highly correlated systems. The class of problems hereis frequently referred to as non-Fermi liquid effects. They lie beyond the edge ofunderstanding of electrons in metals offered by Landau's Fermi liquid theory. Theanomalies beyond the Fermi liquid theory include the large number ofthermodynamic/calorimetric results in rare-earth alloys, which are believed to be near a quantum critical point due to disorder. There are related effects in materials relevant forhigh-density magnetic memories and in relaxor ferroelectrics. There are nonequilibriumeffects such as the high temperature resistivity of high Tc copper oxides. The projectsinvolve analytical and numerical approaches along with close contact with relevantexperimental work.%%%The theoretical work supported in this grant comes from two themes in current research on materials. There are certain anomalies in the properties of electrons in metals, whichApparently lie outside the conventional paradigm, referred to as the Landau's theory ofmetals. They are caused by the presence of substantial disorder and or extremeenvironmental such as pressure, magnetic field or temperature. The work here isfundamental and far-reaching in that it may require development of sophisticated, newmathematical tools and at the same time it is motivated by a need to understand materialswhich are important for high density magnetic memories or materials which use theirferroelectric properties for memory applications. This work will be carried out in closecontact with experimentalists and will make use of both analytical and numericaltechniques, as may be necessary.***