Dynamical Coulomb Blockade as a Local Probe for Quantum Transport

authored by
Jacob Senkpiel, Jan C. Klöckner, Markus Etzkorn, Simon Dambach, Björn Kubala, Wolfgang Belzig, Alfredo Levy Yeyati, Juan Carlos Cuevas, Fabian Pauly, Joachim Ankerhold, Christian R. Ast, Klaus Kern

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.

External Organisation(s)
Max Planck Institute for Solid State Research (MPI-FKF)
Okinawa Institute of Science and Technology Graduate University (OIST)
University of Konstanz
Ulm University
Universidad Autónoma de Madrid
École polytechnique fédérale de Lausanne (EPFL)
Physical review letters
Publication date
Publication status
Peer reviewed
ASJC Scopus subject areas
Physics and Astronomy(all)
Electronic version(s)
https://doi.org/10.1103/PhysRevLett.124.156803 (Access: Open)