短距離秩序を持つ不規則系におけるアンダーソン局在の探索 Search for Anderson Localization in Disordered Svstems with Short Range Order.

澄清液态金属和非晶态金属的异常性质的活动有两个目标。一方面，对数值计算和实验数据进行了详细的比较。在其他谜题中，我们研究了单粒子光谱中赝隙的出现及其对输运性质的影响。松饼-锡均线确实产生了这样的假间隙，随着短程有序的增加，这种假间隙变得越来越明显。因此，输运系数与温度的反常关系是可以预料的。事实上，正如我们的数值结果所显示的那样，这是解释实验观察到的Mooij规则的途径，并且顶点修正增加了电导率在温度下的灵敏度。这也允许自然地解释低温下Q/T的符号(Q是热电势)及其幅度。一个出版物正在准备中(U.Werner和R.Fresard)。作为一个相关的问题，也研究了从金属到绝缘体的转变。如何在从属玻色子泛函积分中处理这一测量已经取得了实质性的成果。由于一个补偿引理，已经展示了如何在这样的泛函积分中处理径向场，并且这项工作将发表(L.Gellhoff和R.Fresard，J.Phys。：Cond.Matt，在新闻发布会上)然后将该引理应用于更复杂的从属玻色子表示，计算了二维Hubbard模型在Mott相变附近的自旋和电荷结构因子。电荷结构因子被发现在弱耦合和强耦合区域(W.Zimmermann，R.Fresard和P.Wolfle，在准备中)与数值模拟是定量一致的。

The goal of the activities on the elucidation of the anomalous properties of liquid and amorphous metals has been two-fold. On the one hand it has been pushed towards a detailed comparison of numerical calculations and experimental data. Among other puzzles we have investigated the occurrence of a pseudo-gap in the one-particle spectrum and its consequences on transport properties. Muffin-tin EMA indeed yields such a pseudo-gap,which becomes more and more pronounced as short-ranged order increases. As a result anomalous temperature dependence of the transport coefficients is expected. Indeed this is the route to the explanation of the experimentally observed Mooij rule as shown by our numerical results,and vertex corrections augment the sensitivity of the conductivity in the temperature. This also allows for a natural explanation of the sign of Q/T (Q being the thermopower),and its amplitude,at low temperature. A publication is in preparation (U.Werner and R.Fresard).As a related problem, metal-to-insulator transitions have also been studied. Substantial achievement on how to handle the measure in slave boson functional integral has been reached. It has been shown how to proceed with radial fields in such functional integrals thanks to a compensation lemma,and the work will be published (L.Gellhoff and R.Fresard,J.Phys. : Cond.Matt.,at press). The lemma has then been applied to more involved slave boson representations,to calculate the spin and charge structure factors of the 2-d Hubbard Model in the vicinity of the Mott transition. The charge structure factor has been found to agree quantitatively with numerical simulations,both in the weak and the strong coupling regimes (W.Zimmermann,R.Fresard and P.Wolfle,in preparation).