Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ferromagnetism in Co7(TeO3)4Br6: A byproduct of complex
  antiferromagnetic order and single-ion anisotropy   Pronounced anisotropy of magnetic properties and complex magnetic order of a
new oxi-halide compound Co7(TeO3)4Br6 has been investigated by powder and
single crystal neutron diffraction, magnetization and ac susceptibility
techniques. Anisotropy of susceptibility extends far into the paramagnetic
temperature range. A principal source of anisotropy are anisotropic properties
of the involved octahedrally coordinated single Co(2+) ions, as confirmed by
angular-overlap-model calculations presented in this work. Incommensurate
antiferromagnetic order sets in at TN=34 K. Propagation vector is strongly
temperature dependent reaching k1=(0.9458(6), 0, 0.6026(5)) at 30 K. A
transition to a ferrimagnetic structure with k2=0 takes place at TC=27 K.
Magnetically ordered phase is characterized by very unusual anisotropy as well:
while M-H scans along b-axis reveals spectacularly rectangular but otherwise
standard ferromagnetic hysteresis loops, M-H studies along other two principal
axes are perfectly reversible, revealing very sharp spin flop (or spin flip)
transitions, like in a standard antiferromagnet (or metamagnet). Altogether,
the observed magnetic phenomenology is interpreted as an evidence of competing
magnetic interactions permeating the system, first of all of the single ion
anisotropy energy and the exchange interactions. Different coordinations of the
Co(2+)-ions involved in the low-symmetry C2/c structure of Co7(TeO3)4Br6 render
the exchange-interaction network very complex by itself. Temperature dependent
changes in the magnetic structure, together with an abrupt emergence of a
ferromagnetic component, are ascribed to continual spin reorientations
described by a multi-component, but yet unknown, spin Hamiltonian.

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The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
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The categories of this paper are: acc-phys
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The categories of this paper are: solv-int
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The categories of this paper are: hep-lat
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The categories of this paper are: stat
21
The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
1
The categories of this paper are: cs
13
The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
3
The categories of this paper are: physics
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The categories of this paper are: patt-sol
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The categories of this paper are: supr-con
2
The categories of this paper are: math
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The categories of this paper are: comp-gas