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Charge-density waves in the Hubbard chain: evidence for 4k_F instability

Thereza Paiva·Raimundo R dos Santos
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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 ρ=1/6 and 1/3; for ρ=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^*(ρ).

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Thereza Paiva, Raimundo R dos Santos. 2000-02-02. Charge-density waves in the Hubbard chain: evidence for 4k_F instability. https://doi.org/10.1103/physrevb.61.13480

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