Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Vortex-Loop Unbinding and Flux-Line Lattice Melting in Superconductors   We study the interplay between a novel vortex-loop unbinding in finite
magnetic field at T=T_V and flux-line lattice (FLL) melting at T=T_M in type-II
superconductors. The FLL melts due to nucleation of vortex loops parallel to
c-axis, connected to flux lines. For moderate anisotropy, phase coherence along
c-axis is lost at T_V > T_M due to an ab-plane vortex-loop unbinding with loops
located close to thermal FLL fluctuations. For large anisotropy, phase
coherence along c-axis is lost at T_V < T_M due to nucleation of ab-plane
vortex-loops uncorrelated to flux lines.

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The categories of this paper are: hep-th
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The categories of this paper are: ao-sci
29
The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
3
The categories of this paper are: physics
11
The categories of this paper are: hep-lat
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The categories of this paper are: cs
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The categories of this paper are: gr-qc
35
The categories of this paper are: mtrl-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: eess
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The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
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The categories of this paper are: econ
28
The categories of this paper are: alg-geom