Atom-molecule coherence in a one-dimensional system
Abstract
We study a model of one-dimensional fermionic atoms that can 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 provide closed form expressions for the density-density response functions.
Cite
@article{arxiv.cond-mat/0505706,
title = {Atom-molecule coherence in a one-dimensional system},
author = {R. Citro and E. Orignac},
journal= {arXiv preprint arXiv:cond-mat/0505706},
year = {2007}
}
Comments
5 pages, no figures, Revtex 4; (v2) added a reference to cond-mat/0505681 where related results are reported; (v3) Expression of correlation functions given in terms of generalized hypergeometric functions