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Quantum Monte Carlo study of the 3D attractive Hubbard model

A. Sewer·X. Zotos·H. Beck
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Abstract

We study the three-dimensional (3D) attractive Hubbard model by means of the Determinant Quantum Monte Carlo method. This model is a prototype for the description of the smooth crossover between BCS superconductivity and Bose-Einstein condensation. By detailed finite-size scaling we extract the finite-temperature phase diagram of the model. In particular, we interpret the observed behavior according to a scenario of two fundamental temperature scales; T* associated with Cooper pair formation and Tc with condensation (giving rise to long-range superconducting order). Our results also indicate the presence of a recently conjectured phase transition hidden by the superconducting state. A comparison with the 2D case is briefly discussed, given its relevance for the physics of high-Tc cuprate superconductors.

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A. Sewer, X. Zotos, H. Beck. 2002-04-02. Quantum Monte Carlo study of the 3D attractive Hubbard model. https://doi.org/10.1103/physrevb.66.140504

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