Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Persistent Dirac Fermion State on Bulk-like Si(111) Surface   The "multilayer silicene" films were grown on Ag(111), with increasing
thickness above 30 monolayers (ML). We found that the "multilayer silicene" is
indeed a bulk Si(111) film. Such Si film on Ag(111) always exhibits a
root(3)xroot(3) honeycomb superstructure on surface. Delocalized surface state
as well as linear energy-momentum dispersion was revealed by quasiparticle
interference patterns (QPI) on the surface, which proves the existence of Dirac
fermions state. Our results indicate that bulk silicon with diamond structure
can also host Dirac fermions, which makes the system even more attractive for
further applications compared with monolayer silicene.

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The categories of this paper are: quant-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: q-fin
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The categories of this paper are: alg-geom
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The categories of this paper are: dg-ga
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The categories of this paper are: nucl-ex
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The categories of this paper are: gr-qc
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The categories of this paper are: math-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: stat
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The categories of this paper are: mtrl-th
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The categories of this paper are: q-alg
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The categories of this paper are: chao-dyn
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The categories of this paper are: solv-int
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The categories of this paper are: nlin
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The categories of this paper are: eess