A ring accelerator for matter-wave solitons

We describe a new technique to accelerate and control a confined cloud of ultracold neutral atoms. In our configuration, a Bose-Einstein Condensate trapped in a ring is accelerated by using an amplitude-modulated optical potential. The spreading of the atomic cloud is avoided by an adequate tuning of the scattering length. We also discuss other variations that offer new possibilities of robust control of atomic solitons. Our numerical results show that this cold matter accelerator is easily accessible in the frame of current experiments.