Quantum Superconductor-Metal Transition in a Proximity Array

A theory of the zero-temperature superconductor-metal transition is developed for an array of superconductive islands (of size d) coupled via a disordered two-dimensional conductor with the dimensionless conductance g = ħ/e²R_□>>1. At T = 0 the macroscopically superconductive state of the array with lattice spacing b>>d is destroyed at g<g_c~0.1²\(b/d\). At high temperatures the normal-state resistance between neighboring islands at b = b_c is much smaller than R_Q = h/4e².