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

S. Schafroth; J. J. Rodriguez; H. Beck

doi:10.1088/0953-8984/9/9/001

paper

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

arXiv:cond-mat/9612246 · doi:10.1088/0953-8984/9/9/001

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.

LaTex, 6 pages, 3 included figures. Accepted for publication in J. Phys: Condensed Matter L9