Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observation of Dirac-like energy band and unusual spectral line shape in
  quasi-one-dimensional superconductor Tl2Mo6Se6   We have performed high-resolution angle-resolved photoemission spectroscopy
of the quasi-one-dimensional (1D) topological superconductor candidate
Tl2Mo6Se6 consisting of weakly-coupled Mo3Se3 chains. We found a quasi-1D Fermi
surface arising from a Dirac-like energy band, which is associated with the
nonsymmorphic screw symmetry of the chains and predicted to trigger topological
superconductivity. We observed a significant spectral-weight reduction over a
wide energy range, together with a tiny Fermi-edge structure which exhibits a
signature of a superconducting-gap opening below the superconducting-transition
temperature. The observed quasi-1D Dirac-like band and its very small density
of states point to an unconventional nature of superconductivity in Tl2Mo6Se6.

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The categories of this paper are: gr-qc
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The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
33
The categories of this paper are: plasm-ph
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The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-lat
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The categories of this paper are: astro-ph
32
The categories of this paper are: atom-ph
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph