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arXiv · 1103.2951

Fulde-Ferrell-Larkin-Ovchinnikov critical polarization in one-dimensional fermionic optical lattices

Vivian V. França·Dominik Hördlein·Andreas Buchleitner
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Abstract

We deduce an expression for the critical polarization P_C below which the FFLO-state emerges in one-dimensional lattices with spin-imbalanced populations. We provide and explore the phase diagram of unconfined chains as a function of polarization, interaction and particle density. For harmonically confined systems we supply a quantitative mapping which allows to apply our phase diagram also for confined chains. We find analytically, and confirm numerically, that the upper bound for the critical polarization is universal: P_C^{max}=1/3 for any density, interaction and confinement strength.

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Vivian V. França, Dominik Hördlein, Andreas Buchleitner. 2012-09-07. Fulde-Ferrell-Larkin-Ovchinnikov critical polarization in one-dimensional fermionic optical lattices. https://doi.org/10.1103/physreva.86.033622

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