ABSTRACT SrTiO3 (STO) thin films of different
thicknesses were deposited on MgAl2O4 (MAO) substrates to
investigate the in-plane strain effect on the soft-mode frequency of the STO
films. X-ray reciprocal space mapping (X-RSM) results indicate that there was
no relaxation of the in-plane lattice strain of the STO films on MAO. Shifts in
the soft-mode frequencies with a decrease in the film thickness were observed
using terahertz time-domain spectroscopy (THz-TDS). However, despite the larger
lattice mismatch between STO and MAO than that between STO and DyScO3 (DSO), the shifts in the soft-mode frequencies of the STO films on MAO were
smaller than those on DSO. The results indicate that the soft-mode frequencies
of the STO films on MAO are affected by the c-axis
Cite this paper
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