Transport, Dynamics, and High Tc

在四种不同的情况下，将从理论上研究凝聚态物质中的热和电的传导。其中两个，高度无序合金中的扩散电输运和绝缘玻璃中的热输运，将由大型计算机对“精确”久保公式的评估来辅助，这些公式旨在测试更简单的近似和阐明输运机制。合金问题使用传统的独立电子模型和Kubo-Greenwood公式。玻璃问题将使用类似的谐波近似和模拟电导率公式，这是以前没有计算出来的。这些项目的目标之一是电阻率的“饱和”，以及金属中电阻率温度系数为负的现象。并对KKR-CPA合金电阻率理论进行了严格的检验。另外两种机制涉及准粒子输运，在传统带费米液态金属和新的氧化物超导体中。对于前者，将使用能带理论从六边形金属的各向异性电阻率中提取耦合常数，并分析霍尔系数。对于后者，将努力通过与实验测量的比较来推断携带电流的准粒子的性质和散射机制。

The conduction of heat and electricity in condensed matter will be studied theoretically in four diverse situations. Two of these, diffusive electrical transport in highly disordered alloys, and heat transport in insulating glasses, will be assisted by large scale computer evaluations of "exact" Kubo formulas designed both to test simpler approximations and to elucidate mechanisms of transport. The alloy problem uses the conventional independent electron model, and the Kubo-Greenwood formula. The glass problem will use the analogous harmonic approximation, and the analog conductivity formula which has not been previously worked out. Among the aims of these projects are "saturation" of resistivity, and the occurrence in metals of negative temperature coefficients of resistivity. Also a rigorous test will be made of the KKR-CPA theory of alloy resistivity. The two other regimes involve quasi-particle transport, in conventional band Fermi liquid metals and in the new oxide superconductors. For the former, band theory will be used to extract coupling constants from the anistropic resistivity of hexagonal metals, and also to analyze the Hall coefficients. For the latter, an effort will be made to deduce the nature of the current carrying quasi-particles and of the scattering mechanisms, by comparison with experimental measurements.