Strongly Interacting Fermi Systems: A Series Expansion Study

通过发展模型哈密顿量的静态和动态性质的级数展开式，将研究强相互作用费米系统的平衡相。这将包括简单的、完全可溶的哈密顿量周围的零温度膨胀，以及高温膨胀。所研究的热力学函数将包括自由能、相关的序参数及其极化率，以及一些特征费米液量，如动量分布函数。此外，还将计算实验上可观察到的动力学参数的频率矩，如自旋晶格驰豫速率、光散射光谱和光学电导。这项工作的结果应该为我们提供一些新的见解，包括磁性和超导有序的存在和相互作用，金属绝缘体的相变，以及费米液体对强关联系统中低能激发的描述的有效性。

Equilibrium phases of strongly interacting Fermi systems will be investigated by developing series expansions for static and dynamic properties of model Hamiltonians. These will include zero temperature expansions around simple exactly soluble Hamiltonians, as well as high temperature expansions. The thermodynamic functions studied will include the free energy, the relevant order parameters and their susceptibilities, and some characteristic Fermi liquid quantities such as the momentum distribution function. In addition, the frequency moments of experimentally observable dynamical quantities such as spin-lattice relaxation rates, the light scattering spectra and the optical conductivity will also be calculated. The results of this work should provide us with novel insight into several condensed matter phenomena including the existence and interplay of magnetic and superconducting order, metal insulator transitions, and the validity of the Fermi liquid description for the low energy excitations in strongly correlated systems.