The BCS-BEC crossover and superconductivity in a lattice fermion model with hard core repulsion

Agnieszka Kujawa

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arXiv · 0808.1374

The BCS-BEC crossover and superconductivity in a lattice fermion model with hard core repulsion

Agnieszka Kujawa

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Abstract

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.

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Agnieszka Kujawa. 2008-08-11. The BCS-BEC crossover and superconductivity in a lattice fermion model with hard core repulsion. https://arxiv.org/abs/0808.1374

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