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Pseudogaps in the 2D half-filled Hubbard model

C. Huscroft·M. Jarrell·Th. Maier·S. Moukouri·A. N. Tahvildarzadeh
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Abstract

We study the pseudogaps in the spectra of the half-filled 2D Hubbard model using both finite-size and dynamical cluster approximation (DCA) quantum Monte Carlo calculations. A charge pseudogap, accompanied by non-Fermi liquid behavior in the self energy, is shown to persist in the thermodynamic limit. The DCA (finite-size) method systematically underestimates (overestimates) the width of the pseudogap. A spin pseudogap is not seen at half-filling.

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C. Huscroft, M. Jarrell, Th. Maier, S. Moukouri, A. N. Tahvildarzadeh. 1999-10-15. Pseudogaps in the 2D half-filled Hubbard model. https://arxiv.org/abs/cond-mat/9910226

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