Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Anomalous impact of hydrostatic pressure on superconductivity of
  polycrystalline LaO0.5F0.5BiSe2   We report bulk superconductivity at 2.5K in LaO0.5F0.5BiSe2 compound through
the DC magnetic susceptibility and electrical resistivity measurements. The
synthesized LaO0.5F0.5BiSe2 compound is crystallized in tetragonal structure
with space group P4/nmm and Reitveld refined lattice parameters are a= 4.15(1)A
and c=14.02(2)A. The lower critical field of Hc1= 40Oe, at temperature 2K is
estimated through the low field magnetization measurements. The LaO0.5F0.5BiSe2
compound showed metallic normal state electrical resistivity with residual
resistivity value of 1.35m{\Omega}-cm. The compound is type-II superconductor,
and the estimated Hc2(0) value obtained by WHH formula is above 20kOe for
90percent Rn criteria. The superconducting transition temperature decreases
with applied pressure till around 1.68GPa and with further higher pressures a
high Tc phase emerges with possible onset Tc of above 5K for 2.5GPa.

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The categories of this paper are: patt-sol
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The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
9
The categories of this paper are: nlin
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The categories of this paper are: mtrl-th
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
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The categories of this paper are: hep-lat
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The categories of this paper are: chao-dyn
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The categories of this paper are: atom-ph
1
The categories of this paper are: cs
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The categories of this paper are: plasm-ph
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The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-alg