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

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.

7 pages, 4 figures

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Cited by in corpus (4)

• Repulsive Fermi polarons with negative effective mass
• Phase-diagram and dynamics of Rydberg-dressed fermions in two-dimensions
• Polarization of a quasi two-dimensional repulsive Fermi gas with Rashba spin-orbit coupling: a variational study
• Energy of strongly attractive Bose-Fermi mixtures