Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A macroscopic persistent current generation by merons in a spin density
  wave ordered state   We show that a stable spontaneous current appears in a system of a spin
density wave order with merons, vortices in the spin configuration with winding
number +1. A meron in the spin density wave order modifies the boundary
condition for eigenfunctions around it to a sign-change one. As a consequence,
two types of stable current states, one with a clockwise circulation and the
other with a counterclockwise one, arise. When a magnetic field is present, one
produces a diamagnetic current is chosen. A collection of such currents results
in a large diamagnetic current; and if the meron density is sufficiently large,
a perfect diamagnetism is realized. The stability of this diamagnetic current
is attributed to the topological nature of the merons, and as long as the
distribution of the merons remains the same the current will persist even in a
macroscopic system.

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The categories of this paper are: alg-geom
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The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
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The categories of this paper are: eess
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The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph
16
The categories of this paper are: stat
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
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The categories of this paper are: chao-dyn
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The categories of this paper are: atom-ph
2
The categories of this paper are: math
7
The categories of this paper are: hep-th
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The categories of this paper are: econ
5
The categories of this paper are: gr-qc
26
The categories of this paper are: bayes-an