The BCS-BEC crossover and superconductivity in a lattice fermion model with hard core repulsion
نویسنده
چکیده
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 = ∞) 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.
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تاریخ انتشار 2008