Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic excitations and anomalous spin wave broadening in multiferroic
  FeV2O4   We report on the different roles of two orbital-active Fe$^{2+}$ at the A
site and V$^{3+}$ at the B site in the magnetic excitations and on the
anomalous spin wave broadening in FeV$_{2}$O$_{4}$. FeV$_{2}$O$_{4}$ exhibits
three structural transitions and successive paramagnetic (PM)-collinear
ferrimagnetic (CFI)-noncollinear ferrimagnetic (NCFI) transitions. The
high-temperature tetragonal/PM -orthorhombic/CFI transition is accompanied by
the appearance of an energy gap with a high magnitude in the magnetic
excitations due to strong spin-orbit coupling induced anisotropy at the
Fe$^{2+}$ site. While there is no measurable increase in the energy gap from
the orbital ordering of V$^{3+}$ at the orthorhombic/CFI-tetragonal/NCFI
transition, anomalous spin wave broadening is observed in the orthorhombic/CFI
state due to V$^{3+}$ spin fluctuations at the B site. The spin wave broadening
is also observed at the zone boundary without softening, which is discussed in
terms of magnon-phonon coupling.

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The categories of this paper are: quant-ph
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The categories of this paper are: eess
1
The categories of this paper are: cs
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
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The categories of this paper are: q-bio
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The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
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The categories of this paper are: physics
34
The categories of this paper are: chem-ph
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The categories of this paper are: adap-org
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The categories of this paper are: nucl-th
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The categories of this paper are: math-ph
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The categories of this paper are: nlin
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The categories of this paper are: gr-qc
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The categories of this paper are: solv-int