Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Studies on the high-temperature ferroelectric transition of multiferroic
  hexagonal manganite RMnO3   Hexagonal manganites are multiferroic materials with two highly-dissimilar
phase transitions: a ferroelectric transition (from P63/mmc to P63cm) at a
temperature higher than 1000 K and an antiferromagnetic transition at TN=65 -
130 K. Despite its critical relevance to the intriguing ferroelectric domain
physics, the details of the ferroelectric transition are yet not well known to
date primarily because of the ultra-high transition temperature. Using
high-temperature X-ray diffraction experiments, we show that the ferroelectric
transition is a single transition of abrupt order and R-Op displacement is the
primary order parameter. This structural transition is then simultaneously
accompanied by MnO5 tilting and the subsequent development of electric
polarization.

17
The categories of this paper are: q-fin
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
34
The categories of this paper are: chem-ph
2
The categories of this paper are: math
11
The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph
12
The categories of this paper are: nucl-th
13
The categories of this paper are: quant-ph
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
19
The categories of this paper are: eess
16
The categories of this paper are: stat