Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Vortex States Induced by Proximity Effect in Hybrid
  Ferromagnet-Superconductor Systems   We consider superconductivity nucleation in multiply connected mesoscopic
samples such as thin-walled cylinders or rings placed in electrical contact
with a ferromagnet. The superconducting critical temperature and order
parameter structure are studied on the basis of linearized Usadel equations. We
suggest a mechanism of switching between the superconducting states with
different vorticities caused by the exchange field and associated with the
oscillatory behavior of the Cooper pair wave function in a ferromagnet.

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The categories of this paper are: q-alg
37
The categories of this paper are: supr-con
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
19
The categories of this paper are: eess
28
The categories of this paper are: alg-geom
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
3
The categories of this paper are: physics
20
The categories of this paper are: acc-phys
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
5
The categories of this paper are: gr-qc
15
The categories of this paper are: nucl-ex
10
The categories of this paper are: q-bio