SOFT-MODE PHONONS in SrTiO3 THIN FILMS STUDIED by FAR-INFRARED ELLIPSOMETRY and RAMAN SCATTERING
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چکیده
We report the experimental studies of the vibrational spectra of SrTiO3 films with the thickness of 1 μm grown by pulsed laser deposition. Fourier-transform infrared ellipsometry between 30 and 700 cm and electric field-induced Raman scattering techniques have been utilized for investigation of the phonon behavior. These results can be used for comparison with the low-frequency measurements of the static dielectric constant. The soft mode in the films reveals hardening compared to that in bulk crystals. This observation is in agreement with the Lyddane-Sachs-Teller formalism.
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تاریخ انتشار 1999