Self-interfering matter-wave patterns generated by a moving laser   obstacle in a two-dimensional Bose-Einstein condensate inside a power trap   cut off by box potential boundaries
  We report the observation of highly energetic self-interfering matter-wave (SIMW) patterns generated by a moving obstacle in a two-dimensional Bose-Einstein condensate (BEC) inside a power trap cut off by hard-wall box potential boundaries. The obstacle initially excites circular dispersive waves radiating away from the center of the trap which are reflected from hard-wall box boundaries at the edges of the trap. The resulting interference between outgoing waves from the center of the trap and reflected waves from the box boundaries institutes, to the best of our knowledge, unprecedented standing wave patterns. For this purpose we simulated the time dependent Gross- Pitaevskii equation using the split-step Crank-Nicolson method. The obstacle is modelled by a moving impenetrable Gaussian potential barrier. Various trapping geometries are considered. 
Roger R. Sakhel, Asaad R. Sakhel, and Humam B. Ghassib
cond-mat.quant-gas