Impact of self-consistency in dual fermion calculations

Article

关键词: HUBBARD-MODEL;    INFINITE DIMENSIONS;   

DOI  :  10.1103/PhysRevB.98.125106

来源: SCIE

【 摘 要 】

The dual fermion (DF) method allows for calculating corrections due to nonlocal correlations relative to an effective impurity model. Choosing the impurity as that of a dynamical mean-field theory (DMFT) solution at self-consistency is popular, and the corrections from dual fermion theory are physically meaningful. We investigate the effect of choosing the impurity instead in a self-consistent manner and find for the two-dimensional Hubbard model an exponential increase of the correlation length and susceptibility at low temperatures. There are pronounced differences for the two self-consistency schemes that are discussed in the literature; the self-consistent DF solution can even be more metallic than the DMFT solution.

【 授权许可】

Free