Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Phase transitions and ferroelectricity in very thin films: single-
  versus multidomain state   We discuss ferroelectric phase transitions into single- and multidomain
states in very thin films using continuous theory. It is shown that in nearly
cubic ferroelectrics the domain state may survive down to atomic film
thicknesses, unlike the single domain state, which is almost always unstable or
metastable. This conclusion is valid almost irrespective of the nature of
electrodes (metallic or semiconducting) and whether or not the screening
carriers may be present in the ferroelectric itself.

34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
5
The categories of this paper are: gr-qc
35
The categories of this paper are: mtrl-th
18
The categories of this paper are: econ
1
The categories of this paper are: cs
29
The categories of this paper are: funct-an
17
The categories of this paper are: q-fin
13
The categories of this paper are: quant-ph
25
The categories of this paper are: patt-sol
0
The categories of this paper are: hep-ph
26
The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci
6
The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
19
The categories of this paper are: eess