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Critical temperature for the two-dimensional attractive Hubbard Model

Thereza Paiva·Raimundo R. dos Santos·R. T. Scalettar·P. J. H. Denteneer
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Abstract

The critical temperature for the attractive Hubbard model on a square lattice is determined from the analysis of two independent quantities, the helicity modulus, $ρ_s$, and the pairing correlation function, $P_s$. These quantities have been calculated through Quantum Monte Carlo simulations for lattices up to $18\times 18$, and for several densities, in the intermediate-coupling regime. Imposing the universal-jump condition for an accurately calculated $ρ_s$, together with thorough finite-size scaling analyses (in the spirit of the phenomenological renormalization group) of $P_s$, suggests that $T_c$ is considerably higher than hitherto assumed.

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Thereza Paiva, Raimundo R. dos Santos, R. T. Scalettar, P. J. H. Denteneer. 2004-03-16. Critical temperature for the two-dimensional attractive Hubbard Model. https://doi.org/10.1103/physrevb.69.184501

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