Evolution and Collision of Bose-Condensed Gas in One-Dimensional Optical Lattices and a Far-Off Resonant Laser Beam

Evolution of a Bose-condensed gas in one-dimensional optical lattices is investigated in the presence of a potential barrier created by a far-off resonant laser beam. After the magnetic trap and optical lattices are switched off, by using the propagator method, the analytical result of the evolution of the density distribution of the Bose-condensed gas is given. In particular, the collision between the condensate and the potential barrier is shown in this paper.