Numerical Evidence of Luttinger and Fermi Liquid Behaviour in the 2D Hubbard Model

Дата и время публикации : 1993-08-02T07:08:21Z

Авторы публикации и институты :
Sandro Sorella

Ссылка на журнал-издание: Ссылка на журнал-издание не найдена
Коментарии к cтатье: 10 pages + 4 pictures, RevTex, SISSA 121/93/CM/MB
Первичная категория: cond-mat

Все категории : cond-mat

Краткий обзор статьи: The two dimensional Hubbard model with a single spin-up electron interacting with a finite density of spin-down electrons is studied using the quantum Monte Carlotechnique, a new conjugate gradient method for the evaluation of the Edwards wavefunction ansatz, and the standard second order perturbation theory. We performed simulations up to 242 sites at $U/t=4$ reaching the zero temperature properties with no “fermion sign problem” and found a surprisingly good accuracy of the Edwards wavefunction ansatz at low density or low doping. The conjugate gradient method was then applied to system up to 1922 sites and infinite $U$ for the Edwards state. Fermi liquid theory seems to remain stable in 2D for all cases studied with the exception of the half filling case where a “Luttinger like behavior” survives in the Hubbard model , yielding a vanishing quasiparticle weight in the thermodynamic limit.

Category: Physics