Ground-state properties of a trapped Bose gas beyond the mean-field approximation - art. no. 063604

We study the effect of interatomic correlations beyond the mean-field appro ximation on the ground-state properties of a trapped Bose gas interacting t hrough a repulsive potential. To this end we employ a variational procedure that is based on the energy functional derived, in the local-density appro ximation, using the low-density expansion for the ground-state energy of th e homogeneous gas. We also make analytic estimates of the corrections due t o the higher-order terms in the expansion. We find that corrections are of the order of 1 %. However, there is a qualitative change in the density pro file for large N (number of atoms) due to presence of a logarithmic term in the expansion.