Dynamical Coulomb Blockade as a Local Probe for Quantum Transport
Abstract
Quantum fluctuations are imprinted with valuable information about transport processes. Experimental access to this information is possible, but challenging. We introduce the dynamical Coulomb blockade (DCB) as a local probe for fluctuations in a scanning tunneling microscope (STM) and show that it provides information about the conduction channels. In agreement with theoretical predictions, we find that the DCB disappears in a single-channel junction with increasing transmission following the Fano factor, analogous to what happens with shot noise. Furthermore we demonstrate local differences in the DCB expected from changes in the conduction channel configuration. Our experimental results are complemented by ab initio transport calculations that elucidate the microscopic nature of the conduction channels in our atomic-scale contacts. We conclude that probing the DCB by STM provides a technique complementary to shot noise measurements for locally resolving quantum transport characteristics.
Keywords
Cite
@article{arxiv.1912.02236,
title = {Dynamical Coulomb Blockade as a Local Probe for Quantum Transport},
author = {Jacob Senkpiel and Jan C. Klöckner and Markus Etzkorn and Simon Dambach and Björn Kubala and Wolfgang Belzig and Alfredo Levy Yeyati and Juan Carlos Cuevas and Fabian Pauly and Joachim Ankerhold and Christian R. Ast and Klaus Kern},
journal= {arXiv preprint arXiv:1912.02236},
year = {2020}
}
Comments
9 pages, 7 figures, including supplementary material