Self-Consistent Second Order Perturbation Theory for the Hubbard Model in Two Dimensions

Abstract

We apply self-consistent second order perturbation theory (SCSOPT) with respect to the on-site repulsive interaction U to study the Hubbard model in two dimensions. We investigate single particle properties of the model over the entire doping range at zero temperature. It is shown that as doping decreases toward half-filling $\omega$-mass enhancement factor increases, while k-mass enhancement factor decreases. The increase in $\omega$-mass enhancement factor is larger than the decrease in k-mass enhancement factor, so that total-mass is larger than that in the non-interacting case. When particle number density per unit cell n is given by 0.64<n<1.0 interaction enhances anisotropy of the Fermi surface, whereas at lower densities n<0.64 interaction suppresses anisotropy of it. Due to the decrease in k-mass enhancement factor the density of states (DOS) at the Fermi level is suppressed. It is possible to understand the results within the framework of the weak coupling Fermi liquid theory.

8 pages, 12 embedded EPS figures, to appear in J. Phys. Soc. Jpn. Vol. 68-3 (1999)

References in corpus (5)

• One-Dimensional Fermi liquids
• Doping Dependent Density of States and Pseudogap Behavior in La2-xSrxCuO4
• Theory for the excitation spectrum of High-T$_c superconductors : quasiparticle dispersion and shadows of the Fermi surface
• Fermi Surface of the 2D Hubbard Model at Weak Coupling
• Perturbation study on the spin and charge susceptibilities of the two-dimensional Hubbard model

Cited by in corpus (5)

• Renormalized perturbation theory for Fermi systems: Fermi surface deformation and superconductivity in the two-dimensional Hubbard model
• Interaction-induced Fermi surface deformations in quasi one-dimensional electronic systems
• On the (anisotropic) uniform metallic ground states of fermions interacting through arbitrary two-body potentials in d dimensions
• Fermi Surface Deformation near Charge-Ordering Transition
• Quasi-particle functional Renormalisation Group calculations in the two-dimensional t-t'-Hubbard model