scholarly journals Strong-coupling perturbation theory of the Hubbard model

2000 ◽  
Vol 16 (1) ◽  
pp. 85-105 ◽  
Author(s):  
S. Pairault ◽  
D. Sénéchal ◽  
A.-M.S. Tremblay
Keyword(s):  
Perturbation Theory ◽  
Hubbard Model ◽  
Strong Coupling

scholarly journals High-order symbolic strong-coupling expansion for the Bose-Hubbard model

2018 ◽  
Vol 98 (24) ◽  
Author(s):  
Tao Wang ◽  
Xue-Feng Zhang ◽  
Chun-Feng Hou ◽  
Sebastian Eggert ◽  
Axel Pelster
Keyword(s):  
Hubbard Model ◽  
Strong Coupling ◽  
Strong Coupling Expansion ◽  
High Order

Hubbard model in the strong-coupling approximation

1993 ◽  
Vol 47 (10) ◽  
pp. 6004-6009 ◽  
Author(s):  
B. M. Elrick ◽  
M. D. Kovarik ◽  
A. E. Jacobs ◽  
W. G. Macready
Keyword(s):  
Hubbard Model ◽  
Strong Coupling ◽  
Coupling Approximation ◽  
Strong Coupling Approximation

η-PAIRING SUPERCONDUCTIVITY IN THE NEGATIVE-U HUBBARD MODEL: EFFECT OF FLUCTUATIONS AND DISORDER

1994 ◽  
Vol 08 (15) ◽  
pp. 2041-2058
Author(s):  
JÜRGEN STEIN
Keyword(s):  
Phase Diagram ◽  
Asymptotic Expansion ◽  
Hubbard Model ◽  
Strong Coupling ◽  
Mean Field ◽  
Higher Order ◽  
Field Phase ◽  
Effective Pair ◽  
The Mean ◽  
Pair Hopping

We have studied the influence of singular fluctuations around the mean-field solution as well as higher order contributions to the geometry controlled asymptotic expansion of the propagators on η-pairing superconductivity in the strong coupling negative-U Hubbard model in the presence of unpaired electrons. The modifications of the mean-field results due to the introduction of disorder and allowance for finite U are also calculated. Besides the singularities already present in the O(2) nonlinear σ-model we find a filling-depending singular depression of the repulsive effective pair-hopping interaction which strongly alters the mean-field phase diagram and appears to suppress the η-pairing phase near the band edges.

Sign in / Sign up

Export Citation Format

Share Document