Effects of disorder on atomic density waves and spin-singlet dimers in one-dimensional optical lattices

摘要

Using the Bethe-ansatz density-functional theory, we study a one-dimensionalHubbard model of confined attractively interacting fermions in the presence ofa uniformly distributed disorder. The strongly-correlated Luther-Emery natureof the attractive one-dimensional Hubbard model is fully taken into account asthe reference system in the density-functional theory. The effects of thedisorder are investigated on the atomic-density waves in theweak-to-intermediate attractive interaction and on the spin-singlet dimers ofdoubly occupied sites in the strongly attractive regime. It is found thatatomic density waves are sensitive to the disorder and the spin-singlet dimersof doubly occupied sites are quite unstable against the disorder. We also showthat very weak disorder could smear the singularities in the stiffness, thussuppress the spin-singlet pairs.