An Integrated First-Principles and Many-Body Theory Description of Electron-Phonon Superconductors

9627778 Freericks/Liu该基金支持乔治城大学凝聚态物理的一个新项目，该项目由两名年轻教师组成，其中一名女性（a . Liu）。该基金支持在米格达尔定理不再有效的情况下，对基于电子-声子相互作用的超导理论进行仔细而详细的分析。这项工作还利用了新的理论工具，这些工具已经为许多大维度（或原子的大配位数）的身体问题开发了新的理论工具。本文提出的工作包括谱密度（SD）的第一性原理计算，用更精确的算法从实验隧道数据中推导出SD，在超导理论中加入顶点校正，并分析晶格非调和性的影响。该基金用于支持乔治敦大学两名在超导理论方面具有互补兴趣和专业知识的年轻教师（一名女性）的合作研究。传统超导体与最近发现的所有超导体（掺杂富勒烯、高Tc材料）之间的主要区别在于，在解释传统材料中的超导性方面如此成功的理论框架，不能应用于新材料。这个项目是考虑相关的困难，并找到解决办法。＊＊＊

9627778 Freericks/Liu This grant supports a new program, consisting of two young faculty members, one female (A. Liu) in condensed matter physics at the Georgetown University. The grant supports work on a careful and detailed analysis of the electron- phonon interaction based theory of superconductivity in the regimes where Migdal's theorem is no longer valid. This work also takes advantage of new theoretical tools that have been developed for many body problems in large dimensions (or alternatively large coordination number for atoms). The work proposed here includes first principles calculation of the spectral densities (SD), derivation of SD from the experimental tunneling data using more accurate algorithm, incorporate vertex corrections in the theory of superconductivity and analyze the effects of lattice anharmonicity. %%% This grant is to support collaborative research of two young faculty (one female) with complementary interests and expertise in the theory of superconductivity at Georgetown University. A major difference between the conventional superconductors and essentially all of the ones that have been discovered recently (doped fullerenes, high Tc materials) is that the theoretical framework, so successful in elucidating superconductivity in conventional materials, cannot be applied to the new materials. This project is to consider the associated difficulties and find solutions for them. ***