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Title: Confinement versus deconfinement of Cooper pairs in one-dimensional spin-3/2 fermionic cold atoms

Abstract

The phase diagram of spin-3/2 fermionic cold atoms trapped in a one-dimensional optical lattice is investigated at quarter filling (one atom per site) by means of large-scale numerical simulations. In full agreement with a recent low-energy approach, we find two phases with confined and deconfined Cooper pairs separated by an Ising quantum phase transition. The leading instability in the confined phase is an atomic-density wave with subdominant quartet superfluid instability made of four fermions. Finally, we reveal the existence of a bond-ordered Mott insulating phase in some part of the repulsive regime.

Authors:
;  [1];  [2];  [3];  [4]
  1. Laboratoire de Physique Theorique, Universite Paul Sabatier, CNRS, 118 Route de Narbonne, 31400 Toulouse (France)
  2. Laboratoire de Physique Theorique de la Matiere Condensee, Universite Pierre et Marie Curie, CNRS, 4 Place Jussieu, 75005 Paris (France)
  3. Laboratoire MPQ, Universite Paris 7, CNRS, 2 Place Jussieu, 75005 Paris (France)
  4. Laboratoire de Physique Theorique et Modelisation, Universite de Cergy-Pontoise, CNRS, 2 Avenue Adolphe Chauvin, 95302 Cergy-Pontoise (France)
Publication Date:
OSTI Identifier:
20957757
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 10; Other Information: DOI: 10.1103/PhysRevB.75.100503; (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; CONFINEMENT; COOPER PAIRS; DENSITY; FERMIONS; INSTABILITY; ISING MODEL; ONE-DIMENSIONAL CALCULATIONS; PHASE DIAGRAMS; PHASE TRANSFORMATIONS; RADIATION PRESSURE; SIMULATION; SPIN; SUPERFLUIDITY; TRAPPING

Citation Formats

Capponi, S., Roux, G., Azaria, P., Boulat, E., and Lecheminant, P. Confinement versus deconfinement of Cooper pairs in one-dimensional spin-3/2 fermionic cold atoms. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.100503.
Capponi, S., Roux, G., Azaria, P., Boulat, E., & Lecheminant, P. Confinement versus deconfinement of Cooper pairs in one-dimensional spin-3/2 fermionic cold atoms. United States. doi:10.1103/PHYSREVB.75.100503.
Capponi, S., Roux, G., Azaria, P., Boulat, E., and Lecheminant, P. Thu . "Confinement versus deconfinement of Cooper pairs in one-dimensional spin-3/2 fermionic cold atoms". United States. doi:10.1103/PHYSREVB.75.100503.
@article{osti_20957757,
title = {Confinement versus deconfinement of Cooper pairs in one-dimensional spin-3/2 fermionic cold atoms},
author = {Capponi, S. and Roux, G. and Azaria, P. and Boulat, E. and Lecheminant, P.},
abstractNote = {The phase diagram of spin-3/2 fermionic cold atoms trapped in a one-dimensional optical lattice is investigated at quarter filling (one atom per site) by means of large-scale numerical simulations. In full agreement with a recent low-energy approach, we find two phases with confined and deconfined Cooper pairs separated by an Ising quantum phase transition. The leading instability in the confined phase is an atomic-density wave with subdominant quartet superfluid instability made of four fermions. Finally, we reveal the existence of a bond-ordered Mott insulating phase in some part of the repulsive regime.},
doi = {10.1103/PHYSREVB.75.100503},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 10,
volume = 75,
place = {United States},
year = {Thu Mar 01 00:00:00 EST 2007},
month = {Thu Mar 01 00:00:00 EST 2007}
}
  • The physical properties of arbitrary half-integer spins F=N-1/2 fermionic cold atoms trapped in a one-dimensional optical lattice are investigated by means of a low-energy approach. Two different superfluid phases are found for F{>=}3/2 depending on whether a discrete symmetry is spontaneously broken or not: an unconfined BCS pairing phase and a confined molecular-superfluid instability made of 2N fermions. We propose an experimental distinction between these phases for a gas trapped in an annular geometry. The confined-unconfined transition is shown to belong to the Z{sub N} generalized Ising universality class. We discuss the possible Mott phases at 1/2N filling.
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