We study the expansion of harmonically trapped bosons in a two-dimensional lattice after suddenly turning off the confining potential. We show that, in the presence of multiple occupancies per lattice site and strong interactions, the system exhibits a clear dynamical separation into slowly and rapidly expanding clouds. We discuss how this effect can be understood within a simple picture by invoking doublons and Bose enhancement. This picture is corroborated by an analysis of the momentum distribution function in the regions with slowly and rapidly expanding bosons.
|Physical Review A - Atomic, Molecular, and Optical Physics
|Published - Sep 30 2013
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics