2ND-ORDER SELF-ENERGY OF THE 2-DIMENSIONAL HUBBARD-MODEL

Authors
DAUL S DZIERZAWA M
Citation
S. Daul et M. Dzierzawa, 2ND-ORDER SELF-ENERGY OF THE 2-DIMENSIONAL HUBBARD-MODEL, Zeitschrift fur Physik. B, Condensed matter, 103(1), 1997, pp. 41-44
Citations number
15
Categorie Soggetti
Physics, Condensed Matter
Journal title
Zeitschrift fur Physik. B, Condensed matter → ACNP
ISSN journal
07223277
Volume
103
Issue
1
Year of publication
1997
Pages
41 - 44
Database
ISI
SICI code
0722-3277(1997)103:1<41:2SOT2H>2.0.ZU;2-R
Abstract
The self-energy Sigma(k,omega) of the 2D Hubbard model on the square l attice is calculated numerically in second order perturbation theory. In the limit of small frequencies the imaginary part of Sigma(k,omega) is also obtained analytically. We find that at half filling Im Sigma( k,omega) similar to omega for k on the Fermi surface, with a logarithm ically divergent prefactor close to the corners k = (0, +/-pi) and (+/ -pi, 0) in agreement with the numerical results.