Momentum interferences of a freely expanding Bose-Einstein condensate in   1D due to interatomic interaction change
  A Bose-Einstein condensate may be prepared in a highly elongated harmonic trap with negligible interatomic interactions using a Feshbach resonance. If a strong repulsive interatomic interaction is switched on and the axial trap is removed to let the condensate evolve freely in the axial direction, a time dependent quantum interference pattern takes place in the short time (Thomas-Fermi) regime, in which the number of peaks of the momentum distribution increases one by one, whereas the spatial density barely changes. 
A. Ruschhaupt, A. del Campo, and J. G. Muga