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arXiv · 1407.8021

Fulde-Ferrell-Larkin-Ovchinnikov state of two-dimensional imbalanced Fermi gases

Daniel E. Sheehy
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Abstract

The ground-state phase diagram of attractively-interacting Fermi gases in two dimensions with a population imbalance is investigated. We find the regime of stability for the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase, in which pairing occurs at finite wave vector, and determine the magnitude of the pairing amplitude $Δ$ and FFLO wavevector $q$ in the ordered phase, finding that $Δ$ can be of the order of the two-body binding energy. Our results rely on a careful analysis of the zero temperature gap equation for the FFLO state, which possesses nonanalyticities as a function of $Δ$ and $q$, invalidating a Ginzburg-Landau expansion in small $Δ$.

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Daniel E. Sheehy. 2015-07-17. Fulde-Ferrell-Larkin-Ovchinnikov state of two-dimensional imbalanced Fermi gases. https://doi.org/10.1103/physreva.92.053631

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