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arXiv · 1404.3898

Zero-Temperature Equation of State and Phase Diagram of Repulsive Fermionic Mixtures

Elisa Fratini·Sebastiano Pilati
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Abstract

We compute the zero-temperature equation of state of a mixture of two fermionic atomic species with repulsive interspecies interactions using second-order perturbation theory. We vary the interaction strength, the population and the mass imbalance, and we analyze the competition between different states: homogeneous, partially separated and fully separated. The canonical phase diagrams are determined for various mass ratios, including the experimentally relevant case of the 6Li-40K mixture. We find substantial differences with respect to the equal-mass case: phase separation occurs at weaker interaction strength, and the partially-separated state can be stable even in the limit of a large majority of heavy atoms. We highlight the effects due to correlations by making comparison with previous mean-field results.

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Elisa Fratini, Sebastiano Pilati. 2014-04-17. Zero-Temperature Equation of State and Phase Diagram of Repulsive Fermionic Mixtures. https://doi.org/10.1103/physreva.90.023605

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