The current flowing from a superconductor to a two-terminal setup describing a nanostructure connected to normal-metal leads is studied. We provide an example of scattering matrix giving ideal splitting off electrons from a Cooper pair by means of Cauchy-Bunyakovsky-Schwarz inequality. The proposal of the junction and its possible variants are discussed in a context of possible experiments.
@article{arxiv.0905.4695,
title = {Maximal positive cross shot noise from Andreev reflection},
author = {A. Bednorz and J. Tworzydło and J. Wróbel and T. Dietl},
journal= {arXiv preprint arXiv:0905.4695},
year = {2009}
}