Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A structural perspective on the origin of the anomalous weak-field
  piezoelectric response at the polymorphic phase boundaries of (Ba, Ca)(Ti,
  M)O3 lead-free piezoelectrics   In this paper, we compare the structural features of Ca modified Ba(Ti, Sn)O3
with that of its Ca-free counterpart to understand why the Ca-modified variant
of this lead-free piezoelectric gives a much higher piezoelectric response. We
found that in spite of the reduced spontaneous lattice strain, the polarization
of the Ca-modified variant is higher. We, therefore, demonstrate that the very
large piezoelectric response of (Ba, Ca)(Ti, Sn)O3 is associated with the
decoupling of the polarization and lattice strain by Ca-modification.

13
The categories of this paper are: quant-ph
29
The categories of this paper are: funct-an
25
The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph
21
The categories of this paper are: adap-org
7
The categories of this paper are: hep-th
18
The categories of this paper are: econ
6
The categories of this paper are: astro-ph
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
37
The categories of this paper are: supr-con
12
The categories of this paper are: nucl-th
15
The categories of this paper are: nucl-ex
23
The categories of this paper are: solv-int