Effects of electron correlation on superconductivity in the Hatsugai-Kohmoto model  

作　　者：Huai-Shuang Zhu Qiang Han 祝怀霜;韩强(Department of Physics,Renmin University of China,Beijing 100872,China)

机构地区：[1]Department of Physics,Renmin University of China,Beijing 100872,China

出　　处：《Chinese Physics B》2021年第10期541-547,共7页中国物理B（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant No.11274379);the Research Funds of Renmin University of China(Grant No.14XNLQ07)。

摘　　要：Understanding how electrons form pairs in the presence of strong electron correlations demands going beyond the BCS paradigm.We study a correlated superconducting model where the correlation effects are accounted for by a U term local in momentum space.The electron correlation is treated exactly while the electron pairing is treated approximately using the mean-field theory.The self-consistent equation for the pair potential is derived and solved.Somewhat contrary to expectation,a weak attractive U comparable to the pair potential can destroy the superconductivity,whereas for weak to intermediate repulsive U,the pair potential can be enhanced.The fidelity of the mean-field ground state is calculated to describe the strength of the elelectron correlation.We show that the pair potential is not equal to the single-electron superconducting gap for the strongly correlated superconductors,in contrast to the uncorrelated BCS limit.

关 键 词：strong correlated superconductivity exactly solvable model mean-field theory 

分 类 号：O469[理学—凝聚态物理]