The BCS-BEC crossover and superconductivity in a lattice fermion model with hard core repulsion
Abstract
Description
We have considered the BCS-BEC crossover at T=0 in the framework of a lattice fermion model (the extended Hubbard model). We have analyzed the case of on-site hard core repulsion ($U=\infty$) and intersite attraction ($W<0$) in a 3D system with extended s-wave pairing symmetry. The mechanisms of density-driven and attraction-strength-driven crossover have been analyzed. We have obtained the ground state phase diagram. The analyzed quantities are: chemical potential, order parameter, coherence length and fraction of condensed particles.
8 pages, 4 figures, Proceedings of the XII National School "Correlated Electron Systems Then and Now", Ustron, September 14-18, 2006
8 pages, 4 figures, Proceedings of the XII National School "Correlated Electron Systems Then and Now", Ustron, September 14-18, 2006