Phase Diagram of a $$^6Li$$ 6 L i – $$^{40}K$$ 40 K Mixture in a Square Lattice

摘要: We calculate the mean-field phase diagram for an attractive interacting Fermi mixture of Lithium-6 ( $$^6Li$$ ) and Potassium-40 $$^{40}K$$ atoms in a two-dimensional optical lattice at finite temperatures. The polarization versus temperature diagrams show that there are three phases: Sarma (in which condensed pairs have zero net momentum), Fulde–Ferrell (FF) non-zero normal Helmholtz free energy is minimized gapless phase). line conventional Bardeen–Cooper–Schrieffer state. contains Lifshitz point. When interaction strength increased, point moves toward higher temperatures larger polarizations. Moreover, contrary to population-imbalanced gas, where separation appears low polarizations, we found existence window FF phase. This means as soon system polarized it goes into if enough. majority compared atoms. also find largest can support before becomes fluid