hide
Free keywords:
Materials Science; Physics; Engineering;
Abstract:
The In/Si(111) system reveals an anisotropy in the electrical
conductivity and is a prototype system for atomic wires on surfaces. We
use this system to study and tune the interwire interaction by
adsorption of oxygen. Through rotational square four-tip transport
measurements, both the parallel (sigma(parallel to)) and perpendicular
(sigma(perpendicular to)) components are measured separately. The
analysis of the I(V) curves reveals that sigma(perpendicular to) is also
affected by adsorption of oxygen, showing clearly an effective interwire
coupling, in agreement with density-functional-theory-based calculations
of the transmittance. In addition to these surface-state mediated
transport channels, we confirm the existence of conducting parasitic
space-charge layer channels and address the importance of substrate
steps by performing the transport measurements of In phases grown on
Si(111) mesa structures.
