Imaging the transition from diffusive to Landauer resistivity dipoles

Physical review. B./Physical review. B, vol. 114

Abstract

A pointlike defect in a uniform current-carrying conductor induces a dipole in the electrochemical potential, which counteracts the original transport field. If the mean free path of the carriers is much smaller than the size of the defect, then the dipole results from the purely diffusive motion of the carriers around the defect. In the opposite limit, ballistic carriers scatter from the defect—for this situation, Landauer postulated the emergence of residual resistivity dipoles that are independent of the defect size and thus impose a fundamental limit on the resistance of the parent conductor. Here, we study resistivity dipoles around holes of different sizes in two-dimensional Bi films on Si(111). Using scanning tunneling potentiometry to image the dipoles, we find a crossover from linear to constant scaling behavior of their amplitudes with defect size, manifesting the transition from diffusive to Landauer dipoles. The extracted parameters of the transition allow us to estimate the Fermi wave vector and the carrier mean free path in our Bi films.

Authors 8

1. Anonymous

   Forschungszentrum Jülich · University of Wrocław · Jülich Aachen Research Alliance

   Affiliation as printed

   Forschungszentrum Jülich

   Jülich Aachen Research Alliance (JARA)

   University of Wrocław

2. David Cuma Aachen

   Forschungszentrum Jülich · Jülich Aachen Research Alliance · RWTH Aachen University

   Affiliation as printed

   Forschungszentrum Jülich

   Jülich Aachen Research Alliance (JARA)

   RWTH Aachen University

3. Timofey Balashov Aachen

   Forschungszentrum Jülich · Jülich Aachen Research Alliance · RWTH Aachen University

   Affiliation as printed

   Forschungszentrum Jülich

   Jülich Aachen Research Alliance (JARA)

   RWTH Aachen University

4. Vasily Cherepanov

   Forschungszentrum Jülich · Jülich Aachen Research Alliance

   Affiliation as printed

   Forschungszentrum Jülich

   Jülich Aachen Research Alliance (JARA)

5. Bert Voigtländer Aachen

   Forschungszentrum Jülich · Jülich Aachen Research Alliance · RWTH Aachen University

   Affiliation as printed

   Forschungszentrum Jülich

   Jülich Aachen Research Alliance (JARA)

   RWTH Aachen University

6. I. Morawski

   University of Wrocław

   Affiliation as printed

   University of Wrocław

7. Frank Stefan Tautz Aachen

   Forschungszentrum Jülich · Jülich Aachen Research Alliance · RWTH Aachen University

   Affiliation as printed

   Forschungszentrum Jülich

   Jülich Aachen Research Alliance (JARA)

   RWTH Aachen University

8. Felix Lüpke

   Forschungszentrum Jülich · University of Cologne · Jülich Aachen Research Alliance

   Affiliation as printed

   Forschungszentrum Jülich

   Jülich Aachen Research Alliance (JARA)

   Universität zu Köln