Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Direct Probing Stacking Order and Electronic Spectrum of Rhombohedral
  Trilayer Graphene with Scanning Tunneling Microscopy   Recently, the rhombohedral trilayer graphene (r-TLG) has attracted much
attention because of its low-energy flat bands, which are predicted to result
in many strongly correlated phenomena. Here, we demonstrate that it is possible
to probe the stacking order and electronic spectrum of the r-TLG directly with
a scanning tunneling microscopy around a monoatomic step edge of the top
graphene layer. The tunneling spectra of the r-TLG exhibit four adjacent peaks,
which are generated by the low-energy flat bands, flanking the charge
neutrality point. Based on these spectra, the true energy gap and the energy
gap at the K-point of the r-TLG are determined as about 9 meV and 23 meV,
respectively. The observed features are well reproduced by a low-energy
effective Hamiltonian.

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The categories of this paper are: physics
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The categories of this paper are: atom-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: q-fin
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-th
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The categories of this paper are: stat
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The categories of this paper are: hep-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: cs
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The categories of this paper are: ao-sci
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The categories of this paper are: comp-gas
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The categories of this paper are: nucl-ex
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The categories of this paper are: cmp-lg
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The categories of this paper are: math
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The categories of this paper are: q-bio