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arXiv · 1208.1194

Pair condensation in the BCS-BEC crossover of ultracold atoms loaded onto a 2D square lattice

Luca Salasnich·Flavio Toigo
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Abstract

We investigate the crossover from the Bardeen-Cooper-Schrieffer (BCS) state of weakly-bound Cooper pairs to the Bose-Einstein Condensate (BEC) of strongly-bound molecular dimers in a gas of ultracold atoms loaded on a two-dimensional optical lattice. By using the the mean-field BCS equations of the emerging Hubbard model and the concept of off-diagonal-long-range-order for fermions we calculate analytically and numerically the pair binding energy, the energy gap and the condensate fraction of Cooper pairs as a function of interaction strength and filling fractor of atoms in the lattice at zero temperature.

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Luca Salasnich, Flavio Toigo. 2012-08-06. Pair condensation in the BCS-BEC crossover of ultracold atoms loaded onto a 2D square lattice. https://doi.org/10.1103/physreva.86.023619

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