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arXiv:1009.3257 · Physical Review A

Stable Fulde-Ferrell-Larkin-Ovchinnikov pairing states in two-dimensional and three-dimensional optical lattices

Zi Cai, Yupeng Wang, Congjun Wu

Published Jun 16, 2011• 47 citations
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Abstract

We present the study of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) pairing states in the $p$-orbital bands in both two- and three-dimensional optical lattices. Due to the quasi-one-dimensional band structure which arises from the unidirectional hopping of the orthogonal $p$ orbitals, the pairing phase space is not affected by spin imbalance. Furthermore, interactions build up high-dimensional phase coherence which stabilizes the FFLO states in 2D and 3D optical lattices in a large parameter regime in the phase diagram. These FFLO phases are stable with the imposition of the inhomogeneous trapping potential. Their entropies are comparable to the normal states at finite temperatures.

DOI
10.1103/physreva.83.063621

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