Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Scanning Tunneling Spectroscopy of Suspended Single-Wall Carbon
  Nanotubes   We have performed low-temperature STM measurements on single-wall carbon
nanotubes that are freely suspended over a trench. The nanotubes were grown by
CVD on a Pt substrate with predefined trenches etched into it. Atomic
resolution was obtained on the freestanding portions of the nanotubes.
Spatially resolved spectroscopy on the suspended portion of both metallic and
semiconducting nanotubes was also achieved, showing a Coulomb-staircase
behavior superimposed on the local density of states. The spacing of the
Coulomb blockade peaks changed with tip position reflecting a changing tip-tube
capacitance.

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The categories of this paper are: patt-sol
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The categories of this paper are: nucl-ex
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn
9
The categories of this paper are: nlin
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The categories of this paper are: eess
12
The categories of this paper are: nucl-th
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The categories of this paper are: plasm-ph
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The categories of this paper are: comp-gas
5
The categories of this paper are: gr-qc
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The categories of this paper are: dg-ga
3
The categories of this paper are: physics
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The categories of this paper are: solv-int
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The categories of this paper are: adap-org
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The categories of this paper are: stat
35
The categories of this paper are: mtrl-th