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
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.
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)
Type: Article
Journal: Physical review letters
Volume: 124
ISSN: 0031-9007
Publication date: 17.04.2020
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: General Physics and Astronomy
Electronic version(s): https://doi.org/10.1103/PhysRevLett.124.156803 (Access: Open)

BibTeX

@article{9b8c062ec0b247ffab03e8b02f51bb4a,
title = "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.",
author = "Jacob Senkpiel and Kl{\"o}ckner, {Jan C.} and Markus Etzkorn and Simon Dambach and Bj{\"o}rn Kubala and Wolfgang Belzig and Yeyati, {Alfredo Levy} and Cuevas, {Juan Carlos} and Fabian Pauly and Joachim Ankerhold and Ast, {Christian R.} and Klaus Kern",
note = "Funding information: We gratefully acknowledge stimulating discussions with Elke Scheer and Alexander Weismann. This work was funded in part by the ERC Consolidator Grant AbsoluteSpin (Grant No. 681164). J. C. K., W. B., and F. P. thank the Collaborative Research Center (SFB) 767 of the Deutsche Forschungsgemeinschaft (DFG) for financial support. Part of the numerical modeling was performed using the computational resources of the bwHPC program, namely, the bwUniCluster and the JUSTUS HPC facility. A. L. Y. and J. C. C. acknowledge funding from the Spanish MINECO (Grants No. FIS2017-84057-P and No. FIS2017-84860-R) and from the “Mar{\'i}a de Maeztu” Programme for Units of Excellence in R&D (MDM-2014-0377). J. A., S. D., and B. K. acknowledge financial support from the Zeiss-Foundation, the Institute for Quantum Science and Technology (IQST), and the Deutsche Forschungsgemeinschaft (DFG) under AN336/11-1.",
year = "2020",
month = apr,
day = "17",
doi = "10.1103/PhysRevLett.124.156803",
language = "English",
volume = "124",
journal = "Physical review letters",
issn = "0031-9007",
publisher = "American Physical Society",
number = "15",
}