Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic phase transitions and unusual antiferromagnetic states in the
  Hubbard model   Ground state magnetic phase diagrams of the square and simple cubic lattices
are investigated for the narrow band Hubbard model within the slave-boson
approach by Kotliar and Ruckenstein. The transitions between saturated
(half-metallic) and non-saturated ferromagnetic phases as well as similar
transition in antiferromagnetic (AFM) state are considered in the
three-dimensional case. Two types of saturated antiferromagnetic state with
different concentration dependences of sublattice magnetization are found in
the two-dimensional case in the vicinity of half-filling: the state with a gap
between AFM subbands and AFM state with large electron mass. The latter state
is hidden by the phase separation in the finite-U case.

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The categories of this paper are: hep-ex
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The categories of this paper are: hep-lat
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The categories of this paper are: hep-th
2
The categories of this paper are: math
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
23
The categories of this paper are: solv-int
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
36
The categories of this paper are: cmp-lg
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg