Self-Consistent Field Theory and Parquet Equations for Correlated Electron Systems

这项续期拨款是为正在进行的相关晶格电子系统的研究提供的。其观点是自洽场近似和拼花理论。这使得Hartree-Fock理论可以推广到具有强关联和大电子涨落的系统。这为精确对角化或模拟等数值技术提供了一种半解析的替代(和检验)方法。除了为这类理论发展重整化群技术外，还将研究与强关联材料(如高T_c超导体)的超导电性和电荷密度有序有关的各种问题。固体的电子结构决定了当前和未来技术所基于的材料的大部分(如果不是全部)共同性质。然而，我们目前对大类材料的了解是相当有限的。其中一类是强关联材料(包括高T_c超导体)，其中电子之间的作用力非常强。这笔赠款资助了一个项目，该项目旨在将一组理论技术扩展到这种新的材料类别，使人们能够理解正常系统的性质。

This renewal grant is for an ongoing study of correlated lattice electron systems. The viewpoint is that of self-consistent-field approximations and parquet theory. This allows the generalization of Hartree-Fock theory to systems having strong correlation and large electronic fluctuations. This provides a semi-analytical alternative (and test) for numerical techniques like exact diagonalization or simulation. In addition to development of renormalization group techniques for this class of theory, various issues concerned with superconductivity and charge-density ordering in strongly correlated materials (such as high-Tc superconductors) will be studied. %%% The electronic structure of solids determines most, if not all, of the common properties of materials on which present and future technology is based. However, there are large classes of materials for which our present understanding is quite limited. One such class is strongly correlated materials (including high-Tc superconductors), in which the forces between electrons are very stong. This grant funds a project intended to extend to this new class of materials a group of theoretical techniques which allow the properties of normal systems to be understood.