Jump to main content
Jump to site search

Issue 31, 2019
Previous Article Next Article

Charge-state assignment of nanoscale single-electron transistors from their current–voltage characteristics

Author affiliations

Abstract

The electronic and magnetic properties of single-molecule transistors depend critically on the molecular charge state. Charge transport in single-molecule transistors is characterized by Coulomb-blocked regions in which the charge state of the molecule is fixed and current is suppressed, separated by high-conductance, sequential-tunneling regions. It is often difficult to assign the charge state of the molecular species in each Coulomb-blocked region due to variability in the work-function of the electrodes. In this work, we provide a simple and fast method to assign the charge state of the molecular species in the Coulomb-blocked regions based on signatures of electron–phonon coupling together with the Pauli-exclusion principle, simply by observing the asymmetry in the current in high-conductance regions of the stability diagram. We demonstrate that charge-state assignments determined in this way are consistent with those obtained from measurements of Zeeman splittings. Our method is applicable at 77 K, in contrast to magnetic-field-dependent measurements, which generally require low temperatures (below 4 K). Due to the ubiquity of electron–phonon coupling in molecular junctions, we expect this method to be widely applicable to single-electron transistors based on single molecules and graphene quantum dots. The correct assignment of charge states allows researchers to better understand the fundamental charge-transport properties of single-molecule transistors.

Graphical abstract: Charge-state assignment of nanoscale single-electron transistors from their current–voltage characteristics

Back to tab navigation

Supplementary files

Publication details

The article was received on 02 May 2019, accepted on 19 Jul 2019 and first published on 22 Jul 2019


Article type: Paper
DOI: 10.1039/C9NR03754C
Nanoscale, 2019,11, 14820-14827

  •   Request permissions

    Charge-state assignment of nanoscale single-electron transistors from their current–voltage characteristics

    B. Limburg, J. O. Thomas, J. K. Sowa, K. Willick, J. Baugh, E. M. Gauger, G. A. D. Briggs, J. A. Mol and H. L. Anderson, Nanoscale, 2019, 11, 14820
    DOI: 10.1039/C9NR03754C

Search articles by author

Spotlight

Advertisements