Shot noise and Coulomb blockade of Andreev reflection

Abstract

We derive low energy effective action for a short coherent conductor between normal (N) and superconducting (S) reservoirs. We evaluate interaction correction $\delta G$ to Andreev conductance and demonstrate a close relation between Coulomb effects and shot noise in NS systems. In the diffusive limit doubling of both shot noise power and charge of the carriers yields $|\delta G|$ four times bigger than in the normal case. Our predictions can be directly tested in future experiments.