We show that in a commensurate bosonic ladder, a quantum phase transition occurs between a Mott insulator and a superfluid when interchain hopping increases. We analyze the properties of this transition as well as the physical properties of the two phases. We discuss the physical consequences for experimental systems such as Josephson Junction arrays.

• Received 15 January 2001

DOI:https://doi.org/10.1103/PhysRevB.63.180508