arXiv:cond-mat/0507043 · Physical Review A

Anderson lattice description of photoassociation in an optical lattice

Takahiko Miyakawa, Pierre Meystre

Published Feb 10, 2006• 6 citations

Abstract

We consider atomic mixtures of bosons and two-component fermions in an optical lattice potential. We show that if the bosons are in a Mott-insulator state with precisely one atom per lattice, the photoassociation of bosonic and fermionic atoms into heteronuclear fermionic molecules is described by the Anderson lattice model. We determine the ground-state properties of an inhomogeneous version of that model in the strong atom-molecule coupling regime, including an additional harmonic trap potential. Various spatial structures arise from the interplay between the atom-molecule correlations and the confining potential. Perturbation theory with respect to the tunneling coupling between fermionic atoms shows that antiferromagnetic correlations develop around a spin-singlet core of fermionic atoms and molecules.

DOI: 10.1103/physreva.73.021601

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