  We study a system of two-dimensional Bose gases trapped in minima of a deep
one-dimensional optical lattice potential. Increasing the tunneling amplitude
between adjacent gases drives a deconfinement transition to a phase where
coherence is established between neighboring two-dimensional gases. We compute
the signature of this transition in the interference pattern of the system as
well as in its rotational response, which provides a direct measurement of the
superfluidity in the system.
