Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic digital flop of ferroelectric domain with fixed spin chirality
  in a triangular lattice helimagnet   Ferroelectric properties in magnetic fields of varying magnitude and
direction have been investigated for a triangular-lattice helimagnet
CuFe1-xGaxO2 (x=0.035). The magnetoelectric phase diagrams were deduced for
magnetic fields along [001], [110], and [1-10] direction, and the in-plane
magnetic field was found to induce the rearrangement of six possible
multiferroic domains. Upon every 60-degree rotation of in-plane magnetic field
around the c-axis, unique 120-degree flop of electric polarization occurs as a
result of the switch of helical magnetic q-vector. The chirality of spin helix
is always conserved upon the q-flop. The possible origin is discussed in the
light of the stable structure of multiferroic domain wall.

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The categories of this paper are: math-ph
31
The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
21
The categories of this paper are: adap-org
33
The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th
27
The categories of this paper are: comp-gas
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
11
The categories of this paper are: hep-lat