Open AccessLOCAL APPROACH IN THE HUBBARD MODEL
Author(s) -
Guozhu Wei,
Nie Hui-Quan,
Kaiyi Zhang
Publication year - 1988
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.37.87
Subject(s) - electronic correlation , antiferromagnetism , hubbard model , physics , ground state , electron , polarization (electrochemistry) , series (stratigraphy) , statistical physics , condensed matter physics , quantum mechanics , superconductivity , chemistry , paleontology , biology
Based on the intraatomic electron correlation and the interatomic electron and spin correlation, the local approach has been used to the Hubbard model. The term〈OOH〉which was neglected in the general calculation is retained in our calculation. Camparing our results with those of the general calculation, we find that when U is large, the effects of the term〈OOH〉in the paramagnetic phase can not be heglected for calculating the correlation energy, the ground state energy, the local moments and the antiferromagnetic polarization around the local moments. To estimate more accurately the electron correlation effects, one has to calculate to higher orders and check he convergency of the series.