physica status solidi (b)

Correlation Effects of the Antiferromagnetic Phase in the Hubbard Model

G. Z. Wel, H. Q. Nie, K. Y. Zhang

Published Nov 1, 1989• 4 citations

Abstract

Abstract Using series expansion of local approach, the electron coupling between nearest‐neighbour sites is considered to investigate the electron correlation effect in the Hubbard model. The results show that when the off‐diagonal elements of the density matrix are considered in the calculation, it leads to an enhancement of double occupancy and are duce of the formation of the local moments.

DOI: 10.1002/pssb.2221560137

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