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arXiv · cond-mat/9612246

Some Global Properties of the Attractive Hubbard Model in the Superconducting Phase: T-Matrix Approximation in 2D

S. Schafroth·J. J. Rodriguez·H. Beck
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Abstract

We have applied the Fast Fourier transform (FFT), which allows to compute efficiently convolution sums, to solve the set of self-consistent T-matrix equations to get the Green function of the two dimensional attractive-U Hubbard modelbelow $T_c$, extending previous calculations of the same authors. Using a constant order parameter $Δ(T)$, we calculated $T_c$ as a function of electron density and interaction strength $U$. These global results deviate from the BCS behavior remarkably.

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S. Schafroth, J. J. Rodriguez, H. Beck. 1996-12-30. Some Global Properties of the Attractive Hubbard Model in the Superconducting Phase: T-Matrix Approximation in 2D. https://doi.org/10.1088/0953-8984%2F9%2F9%2F001

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