Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Control of ferroelectric polarization via uniaxial pressure in the
  spin-lattice-coupled multiferroic CuFe1-xGaxO2   We have demonstrated that ferroelectric polarization in a spin-driven
multiferroic CuFe1-xGaxO2 with x = 0.035 can be controlled by the application
of uniaxial pressure. Our neutron diffraction and in-situ ferroelectric
polarization measurements have revealed that the pressure dependence of the
ferroelectric polarization is explained by repopulation of three types of
magnetic domains originating from the trigonal symmetry of the crystal. We
conclude that the spin-driven anisotropic lattice distortion and the fixed
relationship between the directions of the magnetic modulation wave vector and
the ferroelectric polarization are the keys to this spin-mediated piezoelectric
effect.

2
The categories of this paper are: math
25
The categories of this paper are: patt-sol
28
The categories of this paper are: alg-geom
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
11
The categories of this paper are: hep-lat
18
The categories of this paper are: econ
17
The categories of this paper are: q-fin
27
The categories of this paper are: comp-gas
24
The categories of this paper are: dg-ga
20
The categories of this paper are: acc-phys
22
The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
34
The categories of this paper are: chem-ph