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Single-plane-wave Larkin-Ovchinnikov-Fulde-Ferrell state in BCS--Bose-Einstein condensation crossover

Yan He·Chih-Chun Chien·Qijin Chen·K. Levin
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Abstract

We study the single-plane-wave Larkin-Ovchinnikov-Fulde-Ferrell (LOFF) states for BCS--Bose-Einstein condensation (BEC) crossover at general temperatures $T$. Because we include the important effects of noncondensed pairs, our $T \neq 0$ phase diagrams are different from those reported in earlier work. We find that generalized LOFF phases may be the ground state for a wide range of (weak through moderately strong) interactions, including the unitary regime. However, these LOFF phases are readily destroyed by non-zero $T$.

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Yan He, Chih-Chun Chien, Qijin Chen, K. Levin. 2006-10-26. Single-plane-wave Larkin-Ovchinnikov-Fulde-Ferrell state in BCS--Bose-Einstein condensation crossover. https://doi.org/10.1103/physreva.75.021602

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