Adiabatic transport of Cooper pairs in arrays of Josephson junctions

We have developed a quantitative theory of Cooper pair pumping in gated one -dimensional arrays of Josephson junctions. The pumping accuracy is limited by quantum tunneling of Cooper pairs out of the propagating potential well and by direct supercurrent flow through the array. Both corrections decrea se exponentially with the number N of junctions in the array, but give a se rious limitation of accuracy for any practical array. The supercurrent at r esonant gate voltages decreases with N only as sin(phi/N)/N, where phi is t he Josephson phase difference across the array. [S0163-1829(99)51138-7].