Universal correlations along the BEC-BCS crossover

J. C. Obeso-Jureidini; G. A. Dominguez-Castro; E. Neri; R. Paredes; V. Romero-Rochin

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arXiv · 2211.03832

Universal correlations along the BEC-BCS crossover

J. C. Obeso-Jureidini·G. A. Dominguez-Castro·E. Neri·R. Paredes·V. Romero-Rochin

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Abstract

We show that the long-distance behavior of the two-body density correlation functions and the Cooper-pair probability density of a balanced mixture of a two-component Fermi gas at $T = 0$, is universal along the BEC-BCS crossover. Our result is demonstrated by numerically solving the mean-field BCS model for different finite short-range atomic interaction potentials. We find an analytic expression for the correlation length in terms of the chemical potential and the energy gap at zero momentum.

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J. C. Obeso-Jureidini, G. A. Dominguez-Castro, E. Neri, R. Paredes, V. Romero-Rochin. 2022-11-07. Universal correlations along the BEC-BCS crossover. https://arxiv.org/abs/2211.03832

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