Filling dependence of correlation exponents and metal-Mott insulator transition in strongly correlated electron systems  

作　　者：林明喜 祁胜文 

机构地区：[1]College of Physics and Electronics,Shandong Normal University [2]Department of Physics,Zhejiang Ocean University

出　　处：《Chinese Physics B》2010年第12期484-488,共5页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant No. 10774152);the Natural Science Foundation of Zhejiang Province of China (Grant No. Y1100088);the Founding of Zhejiang Ocean University

摘　　要：Using a universal relation between electron filling factor and ground state energy, this paper studies the dependence of correlation exponents on the electron filling factor of one-dimensional extended Hubbard model in a strong coupling regime, and demonstrates that in contrast to the usual Hubbard model （gc = 1/2）, the dimensionless coupling strength parameter gc heavily depends on the electron filling, and it has a ＂particle-hole＂ symmetry about electron quarter filling point. As increasing the nearest neighbouring repulsive interaction, the single particle spectral weight is transferred from low energy to high energy regimes. Moreover, at electron quarter filling, there is a metal-Mott insulator transition at the strong coupling point gc = 1/4, and this transition is a continuous phase transition.Using a universal relation between electron filling factor and ground state energy, this paper studies the dependence of correlation exponents on the electron filling factor of one-dimensional extended Hubbard model in a strong coupling regime, and demonstrates that in contrast to the usual Hubbard model （gc = 1/2）, the dimensionless coupling strength parameter gc heavily depends on the electron filling, and it has a ＂particle-hole＂ symmetry about electron quarter filling point. As increasing the nearest neighbouring repulsive interaction, the single particle spectral weight is transferred from low energy to high energy regimes. Moreover, at electron quarter filling, there is a metal-Mott insulator transition at the strong coupling point gc = 1/4, and this transition is a continuous phase transition.

关 键 词：strong correlation correlation effect correlation exponent correlation function 

分 类 号：O469[理学—凝聚态物理]