Condensate-mediated dimerization of impurities in atomic BECs

Abstract

We show that strongly correlated impurities confined in an optical lattice can form localized, molecule-like dimer states in the presence of a Bose-Einstein condensate (BEC). By systematically studying the effect of the lattice potential on this mixture, we reveal the two roles of the condensate in assisting the formation of dimerized impurities: mediating the attractive interaction among impurities and rescaling the lattice potential of impurities. At strong coupling between the impurities and the condensate, the two mechanisms cooperate to induce a structural transition, resulting in the rearrangement of dimers. We also show that the nonequilibrium dynamics of these states can be interpreted as a dimerized soliton train.

18 pages, 6 figures