Pedro Brandimarte

Electronic transport in planar atomic-scale structures measured by two-probe scanning tunneling spectroscopy

Nature Communications - 2019    

^* M.K. and P.B. contributed equally

Abstract

Miniaturization of electronic circuits into the single-atom level requires novel approaches to characterize transport properties. Due to its unrivaled precision, scanning probe microscopy is regarded as the method of choice for local characterization of atoms and single molecules supported on surfaces. Here we investigate electronic transport along the anisotropic germanium (001) surface with the use of two-probe scanning tunneling spectroscopy and first-principles transport calculations. We introduce a method for the determination of the transconductance in our two-probe experimental setup and demonstrate how it captures energy-resolved information about electronic transport through the unoccupied surface states. The sequential opening of two transport channels within the quasi-one-dimensional Ge dimer rows in the surface gives rise to two distinct resonances in the transconductance spectroscopic signal, consistent with phase-coherence lengths of up to 50 nm and anisotropic electron propagation. Our work paves the way for the electronic transport characterization of quantum circuits engineered on surfaces.

Press release

Our article was highlighted and discussed at Mapping Ignorance.
It received a scientific hightlight at Centro de Física de Materiales.  
It was selected as a highlight research in 2019 at Donostia International Physics Center.  

Bibtex citation

@Article{Kolmer2019,
  author    = {Marek Kolmer and Pedro Brandimarte and Jakub Lis and Rafal Zuzak and Szymon Godlewski and Hiroyo Kawai and Aran Garcia-Lekue and Nicolas Lorente and Thomas Frederiksen and Christian Joachim and Daniel S{\'{a}}nchez-Portal and Marek Szymonski},
  title     = {Electronic transport in planar atomic-scale structures measured by two-probe scanning tunneling spectroscopy},
  journal   = {Nature Communications},
  year      = {2019},
  volume    = {10},
  number    = {1},
  pages     = {1573}
  doi       = {10.1038/s41467-019-09315-6},
  publisher = {Springer Nature},
}

Key words

• multi-probe scanning tunneling spectroscopy
• planar electronic transport
• semiconducting surface
• multi-terminal simulations
• density functional theory
• non-equilibrium Green's function