Fulde-Ferrell-Larkin-Ovchinnikov pairing in one-dimensional optical lattices

Journal Article · Sun Jun 15 04:00:00 EDT 2008 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PHYSREVB.77.245105· OSTI ID:21143570

Rizzi, M ^[1]; Polini, Marco; Tosi, M P ^[2]; Cazalilla, M A ^[3]; Bakhtiari, M R ^[4]; Fazio, Rosario ^[5]

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1. Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching (Germany)
2. NEST-CNR-INFM, I-56126 Pisa (Italy) and Scuola Normale Superiore, I-56126 Pisa (Italy)
3. Centro de Fisica de Materiales, Centro Mixto CSIC-UPV/EHU, P. Manuel de Lardizabal 3, 20018 San Sebastian (Spain)
4. Nanoscience Center, Department of Physics, University of Jyvaeskylae, P.O. Box 35, 40014 Jyvaeskylae (Finland)
5. International School for Advanced Studies (SISSA), via Beirut 2-4, I-34014 Trieste (Italy)

Spin-polarized attractive Fermi gases in one-dimensional (1D) optical lattices are expected to be remarkably good candidates for the observation of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase. We model these systems with an attractive Hubbard model with population imbalance. By means of the density-matrix renormalization-group method, we compute the pairing correlations as well as the static spin and charge structure factors in the whole range from weak to strong coupling. We demonstrate that pairing correlations exhibit quasi-long-range order and oscillations at the wave number expected from the FFLO theory. However, we also show by numerically computing the mixed spin-charge static structure factor that charge and spin degrees of freedom appear to be coupled already for a small imbalance. We discuss the consequences of this coupling for the observation of the FFLO phase, as well as for the stabilization of the quasi-long-range order into long-range order by coupling many identical 1D systems, such as in quasi-1D optical lattices.

• OSTI ID: 21143570
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Journal Name: Physical Review. B, Condensed Matter and Materials Physics Journal Issue: 24 Vol. 77; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
CORRELATIONS
COUPLING
DEGREES OF FREEDOM
DENSITY MATRIX
ELECTRONS
FERMI GAS
HUBBARD MODEL
LATTICE FIELD THEORY
ONE-DIMENSIONAL CALCULATIONS
OSCILLATIONS
POLARIZATION
RENORMALIZATION
SPIN
SPIN ORIENTATION
STABILIZATION
STRONG-COUPLING MODEL
STRUCTURE FACTORS