Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Effect of epitaxial strain on the spontaneous polarization of thin film
  ferroelectrics   We investigate the variation of the spontaneous ferroelectric polarization
with epitaxial strain for BaTiO$_3$, PbTiO$_3$, LiNbO$_3$, and BiFeO$_3$ using
first principles calculations. We find that while the strain dependence of the
polarization is very strong in the simple perovskite systems BaTiO$_3$ and
PbTiO$_3$ it is only weak in LiNbO$_3$ and BiFeO$_3$. We show that this
different behavior can be understood purely in terms of the piezoelectric and
elastic constants of the unstrained bulk material, and we discuss several
factors that determine the strain behavior of a certain material.

11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
2
The categories of this paper are: math
1
The categories of this paper are: cs
9
The categories of this paper are: nlin
23
The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
6
The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
21
The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg