Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Superconductivity in Metal-Rich Chalcogenide Ta2Se   The metal-metal bond in metal-rich chalcogenide is known to exhibit various
structures and dominate interesting physical properties. Ta2Se can be obtained
by both arc-melting and solid-state pellet methods. Ta2Se crystallizes a
layered tetragonal structure with space group P4/nmm (S.G.129, Pearson symbol
tP6). Each unit cell consists of four layers of body-centered closed packing Ta
atoms sandwiched between two square nets of Se atoms, forming the
Se-Ta-Ta-Ta-Ta-Se networks. A combined result of magnetic susceptibility,
resistivity, and heat capacity measurements on Ta2Se indicate the bulk
superconductivity with Tc = 3.8 (1) K. According to the first-principal
calculations, the d orbitals in Ta atoms dominate the Fermi level in Ta2Se. The
flat bands at gamma-point in the Brillouin zone (BZ) yield to the van Hove
singularities in density of states (DOS) around the Fermi level, which is
intensified by introducing spin-orbit coupling (SOC) effect, thus, could be
critical for the superconductivity in Ta2Se. The physical properties especially
superconductivity is completely different from Ta-rich alloys or transition
metal dichalcogenide TaSe2.

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The categories of this paper are: cs
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The categories of this paper are: atom-ph
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The categories of this paper are: q-bio
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The categories of this paper are: nucl-ex
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The categories of this paper are: nucl-th
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The categories of this paper are: physics
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The categories of this paper are: math
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The categories of this paper are: math-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: acc-phys
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The categories of this paper are: q-alg
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The categories of this paper are: nlin
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The categories of this paper are: adap-org
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The categories of this paper are: hep-lat
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The categories of this paper are: chem-ph
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The categories of this paper are: stat