Physics of Non-Fermi-Liquid Metals

0090071 Si该奖项支持的理论研究集中在：（1）可能与无序协同作用的电子-电子相互作用如何引起在高温超导体、重费米子材料、Si-MOSFET中的稀二维电子气和其它介观结构中具有明显非费米液体特征的低能激发，（2）阐明了真实的材料中的基元激发，在这些材料中，非费米液体行为已被观察到。 提出了四个具体的项目，涉及重费米子的量子临界行为，无序二维系统中的相互作用电子，探测高温超导体中的自旋-电荷分离，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，旨在了解在各种（通常是低维）材料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，因此不符合标准教科书对费米液体的预期。人们对产生这种激发的机制知之甚少。该提案的一部分试图操纵量子点产生理论预测的新型非费米液态，并可能对未来技术的电子设备开发产生影响。 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，并有助于培养下一代科学家，使其掌握最先进的方法，用于具有强电子相关性和无序性的材料。

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.