Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observation of room-temperature ferroelectricity in tetragonal strontium
  titanate thin films on SrTiO3 (001) substrates   We investigated the ferroelectric properties of strontium titanate (STO) thin
films deposited on SrTiO3 (001) substrate with SrRuO3 electrodes. The STO layer
was grown coherently on the SrTiO3 substrate without in-plane lattice
relaxation, but its out-of-plane lattice constant increased with a decrease in
the oxygen pressure during deposition. Using piezoresponse force microscopy and
P-V measurements, we showed that our tetragonal STO films possess
room-temperature ferroelectricity. We discuss the possible origins of the
observed ferroelectricity.

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The categories of this paper are: acc-phys
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The categories of this paper are: chao-dyn
14
The categories of this paper are: math-ph
27
The categories of this paper are: comp-gas
26
The categories of this paper are: bayes-an
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
25
The categories of this paper are: patt-sol
12
The categories of this paper are: nucl-th
1
The categories of this paper are: cs
13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg