arXiv:cond-mat/0002031 · Physical review. B, Condensed matter
Charge-density waves in the Hubbard chain: Evidence for 4kF instability
Thereza Paiva, Raimundo R. dos Santos
Abstract
Charge-density waves in the Hubbard chain are studied by means of finite-temperature quantum Monte Carlo simulations and Lanczos diagonalizations for the ground state. We present results both for the charge susceptibilities and for the charge structure factor at densities $\ensuremath{\rho}=1/6$ and 1/3; for $\ensuremath{\rho}=1/2$ (quarter filled) we only present results for the charge structure factor. The data are consistent with a ${4k}_{F}$ instability dominating over the ${2k}_{F}$ one, at least for sufficiently large values of the Coulomb repulsion U. This can only be reconciled with the Luttinger liquid analyses if the amplitude of the ${2k}_{F}$ contribution vanishes above some ${U}^{*}(\ensuremath{\rho}).$