Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Unravelling the electrical properties of epitaxial Graphene nanoribbons   The size-dependent electrical resistivity of single-layer graphene ribbons
has been studied experimentally for ribbon widths from 16 nm to 320 nm. The
experimental findings are that the resistivity follows a more dramatic trend
than that seen for metallic nanowires of similar dimensions, due to a
combination of surface scattering from the edges, band-gap related effects and
shifts in the Fermi level due to edge effects. We show that the Charge
Neutrality point switches polarity below a ribbon width of around 50 nm, and
that at this point, the thermal coefficient of resistance is a maximum. The
majority doping type therefore can be controlled by altering ribbon width. We
also demonstrate that an alumina passivation layer has a significant effect on
the mean free path of the charge carriers within the graphene, which can be
probed directly via measurements of the width-dependent resistivity. We propose
a model for conduction that takes edge and confinement effects into account.

13
The categories of this paper are: quant-ph
21
The categories of this paper are: adap-org
23
The categories of this paper are: solv-int
3
The categories of this paper are: physics
16
The categories of this paper are: stat
32
The categories of this paper are: atom-ph
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
15
The categories of this paper are: nucl-ex
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an