Nanoscale Electronic Devices
on Carbon Nanotubes
University of California, Berkeley
This is an abstract
for a talk to be given at the
Fifth
Foresight Conference on Molecular Nanotechnology.
The full paper is available here.
Carbon nanotubes constitute a fascinating new class of
materials with potential as nanoscale building blocks for
mechanical, chemical, and electronic applications.
Electronically, the nanotubes are expected to behave as ideal
one-dimensional "quantum wires" with either
semiconducting or metallic behaviors, depending on geometrical
tube parameters. The joining of dissimilar tubes can result in
nonlinear junction devices formed from only a handful of carbon
atoms.
We have used a scanning tunneling microscope (STM) to explore
the local electrical characteristics of single-walled carbon
nanotubes. By moving the STM tip along the length of the
nanotubes, we find well-defined positions where the transport
current changes abruptly from a graphitic response to one that is
highly nonlinear and asymmetrical, including near-perfect
rectification.
The observations are consistent with the existence of
localized, on-tube nanodevices as theoretically predicted for
point defects on carbon nanotubes. The controlled production of
such devices on the otherwise conducting tubes could allow
complex circuits to be fabricated on size scales wholly
inaccessible by current lithographic methods.
*Corresponding Address:
Phillip G. Collins, 366 Le Conte Hall, Berkeley, CA 94720, ph:
(510) 643-9640, fax: (510) 643-8793, [email protected]
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