Physics of Non-Fermi-Liquid Metals

该奖项支持以下理论研究：(1)电子-电子相互作用如何与无序协同作用，在高温超导体、重费米子材料、Si-MOSFET和其他介观结构中产生明显非费米液体性质的低能激发，以及(2)阐明在实际材料中明显观察到非费米液体行为的基本激发。提出了四个具体的计划，包括重费米子的量子临界行为，无序二维系统中的电子相互作用，高温超导体中的自旋-电荷分离的探测，以及介观系统中的非费米液体行为。研究人员将进行理论研究，试图了解在各种(通常是低维)材料上的实验中观察到的不寻常的低能电子激发的性质。这些激发不同于普通金属的激发，因此不符合课本上对费米液体的标准激发期望。能够产生这种兴奋的机制还知之甚少。这项提议的一部分是试图操纵量子点来产生理论上预测的新型非费米液体状态，并可能对为未来技术开发电子设备产生影响。这项研究处于凝聚态理论的前沿，将有助于新理论技术的发展，并将有助于培训下一代科学家使用最先进的方法来处理具有强电子关联和无序的材料。

0090071SiThis award supports theoretical research focused on: (1) how electron-electron interactions, possibly acting in concert with disorder, give rise to low-energy excitations that are distinctly non-Fermi liquid in character in high temperature superconductors, heavy fermion materials, dilute two-dimensional electron gases in Si-MOSFETs, and in other mesoscopic structures, and (2) elucidating the elementary excitations in real materials where non-Fermi liquid behavior has apparently been observed. Four specific projects are proposed involving quantum critical behavior in heavy fermions, interacting electrons in disordered two-dimensional systems, probing spin-charge separation in the high temperature superconductors, and non-Fermi liquid behavior in mesoscopic systems. %%%The investigator will perform theoretical research that seeks to understand the nature of unusual low-energy electronic excitations observed in experiments on a variety of (usually low dimensional) materials. These excitations are not like those of ordinary metals and thus do not fit the standard textbook inspired expectation of a Fermi liquid. The mechanisms that can produce these kinds of excitations are poorly understood. Part of this proposal seeks to manipulate quantum dots to produce novel non-Fermi liquid states predicted by theory and may have bearing on developing electronic devices for a future technology. This research lies at the frontiers of condensed matter theory and will contribute to the development of new theoretical techniques and to the training of the next generation of scientists in state-of-the-art methods for materials with strong electronic correlations and disorder.