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arXiv · 1910.02682

Properties of the low-frequency phonon spectra of ferroelectric barium titanate-based heterostructures

E. D. Gor'kovaya·Yu. A. Tikhonov·V. I. Torgashev·A. S. Mikheykin·I. A. Luk'yanchuk·D. Mezzane·N. Ortega·A. Kumar·R. S. Katiyar·A. G. Razumnaya
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Abstract

Polarized Raman spectra of the epitaxial Ba0.5Sr0.5TiO3 film, bi-color BaTiO3/Ba0.5Sr0.5TiO3 superlattice, and tri-color BaTiO3/Ba0.5Sr0.5TiO3/SrTiO3 superlattice were studied in a broad temperature range of 80-700 K. Based on the temperature dependence of the polar modes we determined the phase transitions temperatures in the studied heterostructures. In the sub-THz frequency range of the Y(XZ)Y spectra, we revealed the coexistence of the Debye-type central peak and soft mode in bi-color BaTiO3/Ba0.5Sr0.5TiO3 superlattice.

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E. D. Gor'kovaya, Yu. A. Tikhonov, V. I. Torgashev, A. S. Mikheykin, I. A. Luk'yanchuk, D. Mezzane, N. Ortega, A. Kumar, R. S. Katiyar, A. G. Razumnaya. 2019-10-07. Properties of the low-frequency phonon spectra of ferroelectric barium titanate-based heterostructures. https://doi.org/10.1080/00150193.2019.1592446

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