The size-effect of Kondo-scattering in nanometer-sized metallic point contacts is measured with the simplified, mechanically-controlled break-junction technique for CuMn alloy of different Mn concentrations: 0.017; 0.035; and 0.18 (±0.017) at.\%. The results are compared with our previous publication on nominally 0.1 at.\% CuMn alloy \cite{1,2}. The increase of width of the Kondo resonance and enhanced ratio of Kondo-peak intensity to electron-phonon scattering intensity is observed for contacts with sizes smaller than 10 nm. From the comparison of electron-phonon scattering intensity for the pressure-type contacts, which correspond to the clean orifice model, we conclude that the size effect is observed in \emph{clean} contacts with the shape of a \emph{channel} (nanowire).
@article{arxiv.1702.03827,
title = {Size-effect of Kondo scattering in point contacts (revisited)},
author = {I. K. Yanson and V. V. Fisun and N. L. Bobrov and J. A. Mydosh and J. M. van Ruitenbeek},
journal= {arXiv preprint arXiv:1702.03827},
year = {2017}
}