  When a tunneling barrier between two superconductors is formed by a normal
material that would be a superconductor in the absence of phase fluctuations,
the resulting Josephson effect can undergo an enormous enhancement. We
establish this novel proximity effect by a general argument as well as a
numerical simulation and argue that it may underlie recent experimental
observations of the giant proximity effect between two cuprate superconductors
separated by a barrier made of the same material rendered normal by severe
underdoping.

Superconductivity;Strongly Correlated Electrons