Hitting a BEC with a comb: Evolution of interference patterns inside a   magnetic trap
  We study the evolution inside a harmonic trap of Bose-Einstein condensates released from the periodic potential of an optical lattice. After a time-of-flight, harmonic motion of the interference peaks is observed as well as a breathing motion in the direction perpendicular to the optical lattice. We interpret these results in terms of a simple physical model and discuss the possibility of more detailed studies of such a system. 
J.H. M\"uller and O. Morsch and M. Cristiani and D. Ciampini and E.   Arimondo