Appearance of effective surface conductivity: An experimental and analytic study

Surface conductance measurements on p-type doped germanium show a small but systematic change to the surface conductivity at different length scales. This effect is independent of the structure of the surface states. We interpret this phenomenon as a manifestation of conductivity changes beneath the...

Full description

Saved in:
Bibliographic Details
Published in:Physical review. B, Condensed matter and materials physics Condensed matter and materials physics, 2015-07, Vol.92 (3), Article 035309
Main Authors: Lis, Jakub, Wojtaszek, Mateusz, Zuzak, Rafal, Such, Bartosz, Szymonski, Marek
Format: Article
Language:English
Subjects:
Asymptotic properties
Condensed matter
Conductance
Current sources
Flow equations
Integrals
Mathematical analysis
Point sources
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Surface conductance measurements on p-type doped germanium show a small but systematic change to the surface conductivity at different length scales. This effect is independent of the structure of the surface states. We interpret this phenomenon as a manifestation of conductivity changes beneath the surface. This hypothesis is confirmed by an analysis of the classical current flow equation. We derive an integral formula for calculating the effective surface conductivity as a function of the distance from a point source. Furthermore, we derive asymptotic values of the surface conductivity at small and large distances. The actual surface conductivity can only be sampled close to the current source. At large distances, the conductivity measured on the surface corresponds to the bulk value.
ISSN:1098-0121
1550-235X
DOI:10.1103/PhysRevB.92.035309