Condensed Matter Seminars

We analyze the ground-state properties of an artificial atom made out of repulsive bosons attracted to a center for the case when all the interactions are short-ranged. The properties of this artificial bosonic atom, which can be created by optically trapping ultracold particles of alkali vapors, can be varied by adjusting both the strength of "nuclear" attraction and the interparticale repulsion. The dependence of the ground-state energy of the atom on the number of particles has a minimum whose position is experimentally tuneable. This implies that the number of bound bosons has a staircase dependence on external parameters which may be used to create a single-atomic pipette -- a set-up allowing the transport of atoms into and out of a reservoir one at a time.