Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Sub-gap spectroscopy of thermally excited quasiparticles in a Nb
  contacted carbon nanotube quantum dot   We present electronic transport measurements of a single wall carbon nanotube
quantum dot coupled to Nb superconducting contacts. For temperatures comparable
to the superconducting gap peculiar transport features are observed inside the
Coulomb blockade and superconducting energy gap regions. The observed
temperature dependence can be explained in terms of sequential tunneling
processes involving thermally excited quasiparticles. In particular, these new
channels give rise to two unusual conductance peaks at zero bias in the
vicinity of the charge degeneracy point and allow to determine the degeneracy
of the ground states involved in transport. The measurements are in good
agreement with model calculations.

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The categories of this paper are: chem-ph
16
The categories of this paper are: stat
19
The categories of this paper are: eess
3
The categories of this paper are: physics
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
32
The categories of this paper are: atom-ph
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The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ
0
The categories of this paper are: hep-ph
7
The categories of this paper are: hep-th
22
The categories of this paper are: chao-dyn
35
The categories of this paper are: mtrl-th