Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Defect-Unbinding Transition in Layered Superconductors   We establish a new interstitial-vacancy unbinding transition of the
Berezinskii-Kosterlitz-Thouless type, transforming the three dimensional
pancake vortex lattice of a decoupled layered superconductor into a defected
solid. This transition is the natural finite-field extension of the
vortex-anti-vortex unbinding transition establishing the zero-field superfluid
stiffness. At finite Josephson coupling, the defect unbinding transition turns
into a topological decoupling transition.

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The categories of this paper are: solv-int
8
The categories of this paper are: hep-ex
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The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
21
The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
25
The categories of this paper are: patt-sol
19
The categories of this paper are: eess
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The categories of this paper are: hep-th
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The categories of this paper are: q-bio
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The categories of this paper are: stat
14
The categories of this paper are: math-ph
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The categories of this paper are: supr-con
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The categories of this paper are: cmp-lg
2
The categories of this paper are: math
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The categories of this paper are: alg-geom