Dynamical self-trapping of Bose-Einstein condensates in shallow optical lattices
Matthias Rosenkranz, Dieter Jaksch, Fong Yin Lim, Weizhu Bao
Abstract
We observe a sudden breakdown of the transport of a strongly repulsive Bose-Einstein condensate through a shallow optical lattice of finite width. By using accurate numerical methods and an analytical description in terms of nonlinear Bloch waves, we attribute this behavior to the development of a self-trapped state. The dependence of this drop on the lattice depth and the interaction strength is investigated. We show that by applying a constant offset potential to the lattice region it is possible to prohibit this self-trapping. We also observe the disappearance of the self-trapped state after a finite time as a result of the finiteness of the lattice.