Atom-Molecule Coherence in a One-Dimensional System
Abstract
We study a model of one-dimensional fermionic atoms with a narrow Feshbach resonance that allows them to bind in pairs to form bosonic molecules. We show that at low energy, a coherence develops between the molecule and fermion Luttinger liquids. At the same time, a gap opens in the spin excitation spectrum. The coherence implies that the order parameters for the molecular Bose-Einstein condensation and the atomic BCS pairing become identical. Moreover, both bosonic and fermionic charge density wave correlations decay exponentially, in contrast with a usual Luttinger liquid. We exhibit a Luther-Emery point where the systems can be described in terms of noninteracting pseudofermions. At this point we discuss the threshold behavior of density-density response functions.
- Publication:
-
Physical Review Letters
- Pub Date:
- September 2005
- DOI:
- 10.1103/PhysRevLett.95.130402
- arXiv:
- arXiv:cond-mat/0505706
- Bibcode:
- 2005PhRvL..95m0402C
- Keywords:
-
- 03.75.Lm;
- 03.75.Mn;
- 71.10.Hf;
- 71.10.Pm;
- Tunneling Josephson effect Bose-Einstein condensates in periodic potentials solitons vortices and topological excitations;
- Multicomponent condensates;
- spinor condensates;
- Non-Fermi-liquid ground states electron phase diagrams and phase transitions in model systems;
- Fermions in reduced dimensions;
- Other;
- Superconductivity
- E-Print:
- 5 pages, no figures, Revtex 4