Visible and infra-red light emitted at a Ag-Ag(111) junction has been investigated from tunneling to single atom contact conditions with a scanning tunneling microscope. The light intensity varies in a highly nonlinear fashion with the conductance of the junction and exhibits a minimum at conductances close to the conductance quantum. The data are interpreted in terms of current noise at optical frequencies, which is characteristic of partially open transport channels.
@article{arxiv.1007.0095,
title = {Optical Probe of Quantum Shot Noise Reduction at a Single-Atom Contact},
author = {Natalia L. Schneider and Guillaume Schull and Richard Berndt},
journal= {arXiv preprint arXiv:1007.0095},
year = {2015}
}