Pressure-dependent Raman modes near the cubic-tetragonal transition in strontium titanate

Date

2018-03-01

Author

KİRACI, ALİ
Yurtseven, Hasan Hamit

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The pressure dependence of the Raman frequency shifts of various Raman modes is calculated at room temperature using the volume data from the literature for the cubic-tetragonal transition in SrTiO3. The isothermal mode Gruneisen parameters of those Raman modes are obtained, which decrease with increasing pressure for this molecular crystal. Calculated Raman frequencies are then used to predict the damping constant and the inverse relaxation time of those Raman modes as a function of pressure by means of the pseudospin-phonon (PS) coupled model and the energy fluctuation (EF) model to describe the cubic-tetragonal transition in SrTiO3. Also, the values of the activation energy are extracted for the Raman modes studied using both models (PS and EF). Our predicted damping constant and the inverse relaxation time for the Raman modes, can be compared with the experimental measurements close to the cubic-tetragonal transition in SrTiO3.

Subject Keywords

Materials Chemistry, Ceramics and Composites

URI

https://hdl.handle.net/11511/46847

Journal

JOURNAL OF THE AMERICAN CERAMIC SOCIETY

DOI

https://doi.org/10.1111/jace.15279

Collections

Department of Physics, Article

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Citation Formats

A. KİRACI and H. H. Yurtseven, “Pressure-dependent Raman modes near the cubic-tetragonal transition in strontium titanate,” JOURNAL OF THE AMERICAN CERAMIC SOCIETY, pp. 1344–1355, 2018, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/46847.