Mott-insulator phase of coupled 1D Bose gases in a 2D optical lattice

Paolo Pedri

Institut für Theoretische Physik, Universität Hannover, Appelstr.2, 30167 Hannover, Germany

We discuss the 2D Mott insulator state of a 2D array of coupled finite size 1D Bose gases. It is shown that the momentum distribution in the lattice plane is very sensitive to the interaction regime in the 1D tubes. In particular, we find that the disappearance of the interference pattern in time of flight experiments will not be a signature of the Mott-insulator phase, but a clear consequence of the strongly interacting Tonks-Girardeau regime along the tubes.