Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: X-ray-induced disordering of the dimerization pattern and apparent
  low-temperature enhancement of lattice symmetry in spinel CuIr$_2$S$_4$   At low temperatures, spinel CuIr$_2$S$_4$ is a charge-ordered spin-dimerized
insulator with triclinic lattice symmetry. We find that x-rays induce a
structural transition in which the local triclinic structure is preserved, but
the average lattice symmetry becomes tetragonal. These structural changes are
accompanied by a thousandfold reduction in the electrical resistivity. The
transition is persistent, but the original state can be restored by thermal
annealing. We argue that x-ray irradiation disorders the lattice dimerization
pattern, producing a state in which the orientation of the dimers is preserved,
but the translational long-range order is destroyed.

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The categories of this paper are: math-ph
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The categories of this paper are: econ
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The categories of this paper are: nucl-ex
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-th
29
The categories of this paper are: funct-an
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The categories of this paper are: math
0
The categories of this paper are: hep-ph
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
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The categories of this paper are: nlin
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The categories of this paper are: q-alg
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The categories of this paper are: alg-geom
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The categories of this paper are: acc-phys
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The categories of this paper are: nucl-th
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The categories of this paper are: gr-qc