Imbalanced Fermi superfluid in a onedimensional optical potential
Abstract
The superfluid properties of a twostate Fermi mixture in an optical lattice are profoundly modified when an imbalance in the population of the two states is present. We present analytical solutions for the free energy and for the gap and number equations in the saddlepoint approximation describing resonant superfluidity in the quasitwodimensional gas. Inhomogeneities due to the trapping potentials can be taken into account using the localdensity approximation. Analyzing the free energy in this approximation, we find that phase separation occurs in the layers. The phase diagram of the superfluid and normal phases is derived, and analytical expressions for the phase lines are presented. We complete the investigation by accounting for effects beyond mean field in the BoseEinstein condensate limit, where the system is more properly described as a BoseFermi mixture of atoms and molecules.
 Authors:
 TFVS, Universiteit Antwerpen, Groenenborgerlaan 171, B2020 Antwerpen (Belgium)
 Publication Date:
 OSTI Identifier:
 20951422
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 18; Other Information: DOI: 10.1103/PhysRevB.75.184526; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANALYTICAL SOLUTION; BOSEEINSTEIN CONDENSATION; DENSITY; FERMI GAS; FREE ENERGY; LAYERS; MEANFIELD THEORY; MIXTURES; ONEDIMENSIONAL CALCULATIONS; PHASE DIAGRAMS; POTENTIALS; SUPERFLUIDITY; TRAPPING; TWODIMENSIONAL CALCULATIONS
Citation Formats
Tempere, J., Wouters, M., and Devreese, J. T. Imbalanced Fermi superfluid in a onedimensional optical potential. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVB.75.184526.
Tempere, J., Wouters, M., & Devreese, J. T. Imbalanced Fermi superfluid in a onedimensional optical potential. United States. doi:10.1103/PHYSREVB.75.184526.
Tempere, J., Wouters, M., and Devreese, J. T. Tue .
"Imbalanced Fermi superfluid in a onedimensional optical potential". United States.
doi:10.1103/PHYSREVB.75.184526.
@article{osti_20951422,
title = {Imbalanced Fermi superfluid in a onedimensional optical potential},
author = {Tempere, J. and Wouters, M. and Devreese, J. T.},
abstractNote = {The superfluid properties of a twostate Fermi mixture in an optical lattice are profoundly modified when an imbalance in the population of the two states is present. We present analytical solutions for the free energy and for the gap and number equations in the saddlepoint approximation describing resonant superfluidity in the quasitwodimensional gas. Inhomogeneities due to the trapping potentials can be taken into account using the localdensity approximation. Analyzing the free energy in this approximation, we find that phase separation occurs in the layers. The phase diagram of the superfluid and normal phases is derived, and analytical expressions for the phase lines are presented. We complete the investigation by accounting for effects beyond mean field in the BoseEinstein condensate limit, where the system is more properly described as a BoseFermi mixture of atoms and molecules.},
doi = {10.1103/PHYSREVB.75.184526},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 18,
volume = 75,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}

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