Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic field-induced phase transitions in a weakly coupled s = 1/2
  quantum spin dimer system Ba$_{3}$Cr$_{2}$O$_{8}$   By using bulk magnetization, electron spin resonance (ESR), heat capacity,
and neutron scattering techniques, we characterize the thermodynamic and
quantum phase diagrams of Ba$_3$Cr$_2$O$_8$. Our ESR measurements indicate that
the low field paramagnetic ground state is a mixed state of the singlet and the
S$_z$ = 0 triplet for $H \perp c$. This suggests the presence of an intra-dimer
Dzyaloshinsky-Moriya (DM) interaction with a DM vector perpendicular to the
c-axis.

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The categories of this paper are: gr-qc
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The categories of this paper are: patt-sol
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The categories of this paper are: acc-phys
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The categories of this paper are: econ
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The categories of this paper are: eess
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The categories of this paper are: plasm-ph
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The categories of this paper are: cs
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The categories of this paper are: nucl-ex
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The categories of this paper are: alg-geom
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The categories of this paper are: chao-dyn
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The categories of this paper are: hep-lat
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The categories of this paper are: funct-an
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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: solv-int
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The categories of this paper are: dg-ga